diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
index 8345b5a..2560af9 100644
--- a/Source/WebCore/ChangeLog
+++ b/Source/WebCore/ChangeLog
@@ -1,3 +1,44 @@
+2019-12-06  Per Arne Vollan  <pvollan@apple.com>
+
+        [iOS] Calls to device orientation API should be done in the UI process
+        https://bugs.webkit.org/show_bug.cgi?id=204720
+
+        Reviewed by Alex Christensen.
+
+        The device orientation API on iOS is communicating with locationd. Since mach lookup to this daemon
+        will be closed, the calls to this API should be moved from the WebContent process to the UI process.
+        This patch implements forwarding of the device orientation requests to the UI process through a new
+        class, DeviceOrientationUpdateProvider, which is subclassed by WebDeviceOrientationUpdateProvider in
+        modern WebKit. This class implements forwarding of the requests to the UI process, and receives
+        device orientation updates from the UI process. An instance of this class will be shared by all
+        device orientation clients on a page, and passed as part of the page configuration parameters. On
+        the UI process side, a new class WebDeviceOrientationUpdateProviderProxy attached to the Web page
+        proxy is taking care of calling the device orientation API through the existing WebCoreMotionManager
+        Objective-C class, and send device orientation updates back to the Web process. Also, use a weak
+        hash set of orientation clients in WebCoreMotionManager.
+
+        * WebCore.xcodeproj/project.pbxproj:
+        * dom/DeviceOrientationClient.h:
+        * dom/Document.cpp:
+        * page/Page.cpp:
+        (WebCore::m_deviceOrientationUpdateProvider):
+        (WebCore::m_applicationManifest): Deleted.
+        * page/Page.h:
+        (WebCore::Page::deviceOrientationUpdateProvider const):
+        * page/PageConfiguration.h:
+        * platform/ios/DeviceOrientationClientIOS.h:
+        * platform/ios/DeviceOrientationClientIOS.mm:
+        (WebCore::DeviceOrientationClientIOS::DeviceOrientationClientIOS):
+        (WebCore::DeviceOrientationClientIOS::startUpdating):
+        (WebCore::DeviceOrientationClientIOS::stopUpdating):
+        (WebCore::DeviceOrientationClientIOS::deviceOrientationControllerDestroyed):
+        * platform/ios/WebCoreMotionManager.h:
+        * platform/ios/WebCoreMotionManager.mm:
+        (-[WebCoreMotionManager addOrientationClient:]):
+        (-[WebCoreMotionManager removeOrientationClient:]):
+        (-[WebCoreMotionManager checkClientStatus]):
+        (-[WebCoreMotionManager sendMotionData:withHeading:]):
+
 2019-12-06  Sihui Liu  <sihui_liu@apple.com>
 
         IndexedDB: pass along error of IDBBackingStore::renameIndex
diff --git a/Source/WebCore/WebCore.xcodeproj/project.pbxproj b/Source/WebCore/WebCore.xcodeproj/project.pbxproj
index 2b61f35..3b86bbe 100644
--- a/Source/WebCore/WebCore.xcodeproj/project.pbxproj
+++ b/Source/WebCore/WebCore.xcodeproj/project.pbxproj
@@ -909,7 +909,7 @@
 		3135910A1E7DDC7300F30630 /* RTCSdpType.h in Headers */ = {isa = PBXBuildFile; fileRef = 313591041E7DDC6000F30630 /* RTCSdpType.h */; };
 		3135910B1E7DDC7300F30630 /* RTCSignalingState.h in Headers */ = {isa = PBXBuildFile; fileRef = 313591051E7DDC6000F30630 /* RTCSignalingState.h */; };
 		313BCE1C235E3BE500FC39E5 /* ElementContext.h in Headers */ = {isa = PBXBuildFile; fileRef = 313BCE1B235E3BDB00FC39E5 /* ElementContext.h */; settings = {ATTRIBUTES = (Private, ); }; };
-		3140379B124BEA7F00AF40E4 /* WebCoreMotionManager.h in Headers */ = {isa = PBXBuildFile; fileRef = 31403797124BEA7F00AF40E4 /* WebCoreMotionManager.h */; };
+		3140379B124BEA7F00AF40E4 /* WebCoreMotionManager.h in Headers */ = {isa = PBXBuildFile; fileRef = 31403797124BEA7F00AF40E4 /* WebCoreMotionManager.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		3140379D124BEA7F00AF40E4 /* DeviceOrientationClientIOS.h in Headers */ = {isa = PBXBuildFile; fileRef = 31403799124BEA7F00AF40E4 /* DeviceOrientationClientIOS.h */; };
 		3140C5201FDF151A00D2A873 /* OffscreenCanvasRenderingContext2D.h in Headers */ = {isa = PBXBuildFile; fileRef = 3140C51E1FDF151A00D2A873 /* OffscreenCanvasRenderingContext2D.h */; };
 		3140C5241FDF318700D2A873 /* CanvasRenderingContext2DBase.h in Headers */ = {isa = PBXBuildFile; fileRef = 3140C5221FDF318600D2A873 /* CanvasRenderingContext2DBase.h */; };
@@ -4780,6 +4780,8 @@
 		E35802B61DC8435D00A9773C /* DOMJITIDLTypeFilter.h in Headers */ = {isa = PBXBuildFile; fileRef = E35802B51DC8435800A9773C /* DOMJITIDLTypeFilter.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E377FE4D1DADE16500CDD025 /* NodeConstants.h in Headers */ = {isa = PBXBuildFile; fileRef = E3D049931DADC04500718F3C /* NodeConstants.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E37C86501EB63E3F0087C6CA /* JSDOMPromise.h in Headers */ = {isa = PBXBuildFile; fileRef = E37C864F1EB63E2D0087C6CA /* JSDOMPromise.h */; settings = {ATTRIBUTES = (Private, ); }; };
+		E39628BF2395728F00658ECD /* DeviceOrientationUpdateProvider.h in Headers */ = {isa = PBXBuildFile; fileRef = E39628BD2395728E00658ECD /* DeviceOrientationUpdateProvider.h */; settings = {ATTRIBUTES = (Private, ); }; };
+		E39628C12395743100658ECD /* MotionManagerClient.h in Headers */ = {isa = PBXBuildFile; fileRef = E39628C02395743000658ECD /* MotionManagerClient.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E3A776671DC85D2800B690D8 /* DOMJITIDLConvert.h in Headers */ = {isa = PBXBuildFile; fileRef = E3A776651DC85D2200B690D8 /* DOMJITIDLConvert.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E3A776681DC85D2800B690D8 /* DOMJITIDLType.h in Headers */ = {isa = PBXBuildFile; fileRef = E3A776661DC85D2200B690D8 /* DOMJITIDLType.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		E3B2F0ED1D7F4CA300B0C9D1 /* LoadableScript.h in Headers */ = {isa = PBXBuildFile; fileRef = E3B2F0E71D7F35EC00B0C9D1 /* LoadableScript.h */; settings = {ATTRIBUTES = (Private, ); }; };
@@ -15084,6 +15086,8 @@
 		E38838941BAD145F00D62EE3 /* ScriptModuleLoader.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = ScriptModuleLoader.cpp; sourceTree = "<group>"; };
 		E38838951BAD145F00D62EE3 /* ScriptModuleLoader.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ScriptModuleLoader.h; sourceTree = "<group>"; };
 		E38D06091F8E811900649CF2 /* ModuleFetchParameters.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ModuleFetchParameters.h; sourceTree = "<group>"; };
+		E39628BD2395728E00658ECD /* DeviceOrientationUpdateProvider.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = DeviceOrientationUpdateProvider.h; sourceTree = "<group>"; };
+		E39628C02395743000658ECD /* MotionManagerClient.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = MotionManagerClient.h; sourceTree = "<group>"; };
 		E3975B761EC9AF3900847717 /* JSDocumentFragmentDOMJIT.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = JSDocumentFragmentDOMJIT.cpp; sourceTree = "<group>"; };
 		E3975B771EC9AF3900847717 /* JSElementDOMJIT.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = JSElementDOMJIT.cpp; sourceTree = "<group>"; };
 		E3975B781EC9AF3900847717 /* JSEventDOMJIT.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = JSEventDOMJIT.cpp; sourceTree = "<group>"; };
@@ -22814,6 +22818,7 @@
 				31EAF97D121435A400E7C1BF /* DeviceMotionClientIOS.mm */,
 				31403799124BEA7F00AF40E4 /* DeviceOrientationClientIOS.h */,
 				3140379A124BEA7F00AF40E4 /* DeviceOrientationClientIOS.mm */,
+				E39628BD2395728E00658ECD /* DeviceOrientationUpdateProvider.h */,
 				0FDA7C22188330A900C954B5 /* DragImageIOS.mm */,
 				265541371489811C000DFC5D /* KeyEventCodesIOS.h */,
 				265541381489811C000DFC5D /* KeyEventIOS.mm */,
@@ -22830,6 +22835,7 @@
 				1C43DE6822AB4B8A001527D9 /* LocalCurrentTraitCollection.h */,
 				1C43DE6A22AB4B8A001527D9 /* LocalCurrentTraitCollection.mm */,
 				46EFAF0D1E5FB9C200E7F34B /* LowPowerModeNotifierIOS.mm */,
+				E39628C02395743000658ECD /* MotionManagerClient.h */,
 				E45390190EAFCACA003695C8 /* PasteboardIOS.mm */,
 				26601EBD14B3B9AD0012C0FE /* PlatformEventFactoryIOS.h */,
 				26601EBE14B3B9AD0012C0FE /* PlatformEventFactoryIOS.mm */,
@@ -29555,6 +29561,7 @@
 				59A85EA4119D68EC00DEF1EF /* DeviceOrientationEvent.h in Headers */,
 				460E3075222F4EFD009A0606 /* DeviceOrientationOrMotionEvent.h in Headers */,
 				460E3077222F4F03009A0606 /* DeviceOrientationOrMotionPermissionState.h in Headers */,
+				E39628BF2395728F00658ECD /* DeviceOrientationUpdateProvider.h in Headers */,
 				572B401F21757A64000AD43E /* DeviceRequestConverter.h in Headers */,
 				572B403A21772581000AD43E /* DeviceResponseConverter.h in Headers */,
 				267725FD1A5B3AD9003C24DD /* DFA.h in Headers */,
@@ -31442,6 +31449,7 @@
 				709A01FE1E3D0BDD006B0D4C /* ModuleFetchFailureKind.h in Headers */,
 				E3201C1A1F8E82130076A032 /* ModuleFetchParameters.h in Headers */,
 				F55B3DC61251F12D003EF269 /* MonthInputType.h in Headers */,
+				E39628C12395743100658ECD /* MotionManagerClient.h in Headers */,
 				85031B460A44EFC700F992E0 /* MouseEvent.h in Headers */,
 				83765F951DAC522F00C06537 /* MouseEventInit.h in Headers */,
 				935C476309AC4CE600A6AAB4 /* MouseEventWithHitTestResults.h in Headers */,
diff --git a/Source/WebCore/dom/DeviceOrientationClient.h b/Source/WebCore/dom/DeviceOrientationClient.h
index 67ee4c9..2a26562 100644
--- a/Source/WebCore/dom/DeviceOrientationClient.h
+++ b/Source/WebCore/dom/DeviceOrientationClient.h
@@ -28,6 +28,7 @@
 
 #include "DeviceClient.h"
 #include <wtf/Noncopyable.h>
+#include <wtf/RefPtr.h>
 
 namespace WebCore {
 
diff --git a/Source/WebCore/dom/Document.cpp b/Source/WebCore/dom/Document.cpp
index a8dfbdc..af688c7 100644
--- a/Source/WebCore/dom/Document.cpp
+++ b/Source/WebCore/dom/Document.cpp
@@ -565,7 +565,7 @@
 #if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
     , m_deviceMotionClient(makeUnique<DeviceMotionClientIOS>())
     , m_deviceMotionController(makeUnique<DeviceMotionController>(*m_deviceMotionClient))
-    , m_deviceOrientationClient(makeUnique<DeviceOrientationClientIOS>())
+    , m_deviceOrientationClient(makeUnique<DeviceOrientationClientIOS>(page() ? page()->deviceOrientationUpdateProvider() : nullptr))
     , m_deviceOrientationController(makeUnique<DeviceOrientationController>(*m_deviceOrientationClient))
 #endif
     , m_pendingTasksTimer(*this, &Document::pendingTasksTimerFired)
diff --git a/Source/WebCore/page/Page.cpp b/Source/WebCore/page/Page.cpp
index 3bea9d8..5655dc2 100644
--- a/Source/WebCore/page/Page.cpp
+++ b/Source/WebCore/page/Page.cpp
@@ -288,6 +288,9 @@
 #if ENABLE(APPLICATION_MANIFEST)
     , m_applicationManifest(pageConfiguration.applicationManifest)
 #endif
+#if ENABLE(DEVICE_ORIENTATION) && PLATFORM(IOS_FAMILY)
+    , m_deviceOrientationUpdateProvider(WTFMove(pageConfiguration.deviceOrientationUpdateProvider))
+#endif
 {
     updateTimerThrottlingState();
 
diff --git a/Source/WebCore/page/Page.h b/Source/WebCore/page/Page.h
index 0171238..6505af7 100644
--- a/Source/WebCore/page/Page.h
+++ b/Source/WebCore/page/Page.h
@@ -69,6 +69,10 @@
 #include "MediaPlaybackTargetContext.h"
 #endif
 
+#if ENABLE(DEVICE_ORIENTATION) && PLATFORM(IOS_FAMILY)
+#include "DeviceOrientationUpdateProvider.h"
+#endif
+
 namespace JSC {
 class Debugger;
 }
@@ -723,6 +727,10 @@
 
     WEBCORE_EXPORT Vector<Ref<Element>> editableElementsInRect(const FloatRect&) const;
 
+#if ENABLE(DEVICE_ORIENTATION) && PLATFORM(IOS_FAMILY)
+    DeviceOrientationUpdateProvider* deviceOrientationUpdateProvider() const { return m_deviceOrientationUpdateProvider.get(); }
+#endif
+
 private:
     struct Navigation {
         RegistrableDomain domain;
@@ -995,6 +1003,10 @@
 
     Optional<ViewportArguments> m_overrideViewportArguments;
 
+#if ENABLE(DEVICE_ORIENTATION) && PLATFORM(IOS_FAMILY)
+    RefPtr<DeviceOrientationUpdateProvider> m_deviceOrientationUpdateProvider;
+#endif
+
     bool m_shouldEnableICECandidateFilteringByDefault { true };
     bool m_mediaPlaybackIsSuspended { false };
     bool m_mediaBufferingIsSuspended { false };
diff --git a/Source/WebCore/page/PageConfiguration.h b/Source/WebCore/page/PageConfiguration.h
index 4d953f1..1936592 100644
--- a/Source/WebCore/page/PageConfiguration.h
+++ b/Source/WebCore/page/PageConfiguration.h
@@ -118,6 +118,10 @@
     RefPtr<StorageNamespaceProvider> storageNamespaceProvider;
     RefPtr<UserContentProvider> userContentProvider;
     RefPtr<VisitedLinkStore> visitedLinkStore;
+    
+#if ENABLE(DEVICE_ORIENTATION) && PLATFORM(IOS_FAMILY)
+    RefPtr<DeviceOrientationUpdateProvider> deviceOrientationUpdateProvider;
+#endif
 };
 
 }
diff --git a/Source/WebCore/platform/ios/DeviceOrientationClientIOS.h b/Source/WebCore/platform/ios/DeviceOrientationClientIOS.h
index 1c5701f..eb50544 100644
--- a/Source/WebCore/platform/ios/DeviceOrientationClientIOS.h
+++ b/Source/WebCore/platform/ios/DeviceOrientationClientIOS.h
@@ -30,15 +30,17 @@
 #include "DeviceOrientationClient.h"
 #include "DeviceOrientationController.h"
 #include "DeviceOrientationData.h"
+#include "DeviceOrientationUpdateProvider.h"
+#include "MotionManagerClient.h"
 #include <wtf/RefPtr.h>
 
 OBJC_CLASS WebCoreMotionManager;
 
 namespace WebCore {
 
-class DeviceOrientationClientIOS : public DeviceOrientationClient {
+class DeviceOrientationClientIOS : public DeviceOrientationClient, public MotionManagerClient {
 public:
-    DeviceOrientationClientIOS();
+    DeviceOrientationClientIOS(RefPtr<DeviceOrientationUpdateProvider>&&);
     ~DeviceOrientationClientIOS() override;
     void setController(DeviceOrientationController*) override;
     void startUpdating() override;
@@ -46,13 +48,14 @@
     DeviceOrientationData* lastOrientation() const override;
     void deviceOrientationControllerDestroyed() override;
 
-    void orientationChanged(double, double, double, double, double);
+    void orientationChanged(double, double, double, double, double) override;
 
 private:
-    WebCoreMotionManager* m_motionManager;
-    DeviceOrientationController* m_controller;
+    WebCoreMotionManager* m_motionManager  { nullptr };
+    DeviceOrientationController* m_controller  { nullptr };
     RefPtr<DeviceOrientationData> m_currentDeviceOrientation;
-    bool m_updating;
+    RefPtr<DeviceOrientationUpdateProvider> m_deviceOrientationUpdateProvider;
+    bool m_updating { false };
 };
 
 } // namespace WebCore
diff --git a/Source/WebCore/platform/ios/DeviceOrientationClientIOS.mm b/Source/WebCore/platform/ios/DeviceOrientationClientIOS.mm
index 16a0142..6bd7490 100644
--- a/Source/WebCore/platform/ios/DeviceOrientationClientIOS.mm
+++ b/Source/WebCore/platform/ios/DeviceOrientationClientIOS.mm
@@ -33,10 +33,9 @@
 
 namespace WebCore {
 
-DeviceOrientationClientIOS::DeviceOrientationClientIOS()
+DeviceOrientationClientIOS::DeviceOrientationClientIOS(RefPtr<DeviceOrientationUpdateProvider>&& deviceOrientationUpdateProvider)
     : DeviceOrientationClient()
-    , m_motionManager(nullptr)
-    , m_updating(0)
+    , m_deviceOrientationUpdateProvider(WTFMove(deviceOrientationUpdateProvider))
 {
 }
 
@@ -53,6 +52,11 @@
 {
     m_updating = true;
 
+    if (m_deviceOrientationUpdateProvider) {
+        m_deviceOrientationUpdateProvider->startUpdating(*this);
+        return;
+    }
+
     if (!m_motionManager)
         m_motionManager = [WebCoreMotionManager sharedManager];
 
@@ -63,6 +67,11 @@
 {
     m_updating = false;
 
+    if (m_deviceOrientationUpdateProvider) {
+        m_deviceOrientationUpdateProvider->stopUpdating(*this);
+        return;
+    }
+
     // Remove ourselves as the orientation client so we won't get updates.
     [m_motionManager removeOrientationClient:this];
 }
@@ -74,6 +83,11 @@
 
 void DeviceOrientationClientIOS::deviceOrientationControllerDestroyed()
 {
+    if (m_deviceOrientationUpdateProvider) {
+        m_deviceOrientationUpdateProvider->stopUpdating(*this);
+        return;
+    }
+
     [m_motionManager removeOrientationClient:this];
 }
     
diff --git a/Source/WebCore/platform/ios/DeviceOrientationUpdateProvider.h b/Source/WebCore/platform/ios/DeviceOrientationUpdateProvider.h
new file mode 100644
index 0000000..c731207
--- /dev/null
+++ b/Source/WebCore/platform/ios/DeviceOrientationUpdateProvider.h
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2019 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+
+#include <wtf/RefCounted.h>
+
+namespace WebCore {
+
+class MotionManagerClient;
+
+class DeviceOrientationUpdateProvider : public RefCounted<DeviceOrientationUpdateProvider> {
+public:
+    virtual ~DeviceOrientationUpdateProvider() { }
+
+    virtual void startUpdating(MotionManagerClient&) = 0;
+    virtual void stopUpdating(MotionManagerClient&) = 0;
+
+    virtual void deviceOrientationChanged(double, double, double, double, double) = 0;
+    
+protected:
+    DeviceOrientationUpdateProvider() = default;
+};
+
+} // namespace WebCore
+
+#endif // PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
diff --git a/Source/WebCore/platform/ios/MotionManagerClient.h b/Source/WebCore/platform/ios/MotionManagerClient.h
new file mode 100644
index 0000000..62974cb
--- /dev/null
+++ b/Source/WebCore/platform/ios/MotionManagerClient.h
@@ -0,0 +1,43 @@
+/*
+* Copyright (C) 2019 Apple Inc. All rights reserved.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions
+* are met:
+* 1. Redistributions of source code must retain the above copyright
+*    notice, this list of conditions and the following disclaimer.
+* 2. Redistributions in binary form must reproduce the above copyright
+*    notice, this list of conditions and the following disclaimer in the
+*    documentation and/or other materials provided with the distribution.
+*
+* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+* THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#pragma once
+
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+
+#include <wtf/WeakPtr.h>
+
+namespace WebCore {
+
+class MotionManagerClient : public CanMakeWeakPtr<MotionManagerClient> {
+public:
+    virtual ~MotionManagerClient() { };
+
+    virtual void orientationChanged(double, double, double, double, double) = 0;
+};
+
+};
+
+#endif // PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
diff --git a/Source/WebCore/platform/ios/WebCoreMotionManager.h b/Source/WebCore/platform/ios/WebCoreMotionManager.h
index 86b170c..cfc668d 100644
--- a/Source/WebCore/platform/ios/WebCoreMotionManager.h
+++ b/Source/WebCore/platform/ios/WebCoreMotionManager.h
@@ -25,10 +25,9 @@
 
 #pragma once
 
-#import "DeviceMotionClientIOS.h"
-#import "DeviceOrientationClientIOS.h"
 #import <CoreLocation/CoreLocation.h>
 #import <wtf/HashCountedSet.h>
+#import <wtf/WeakHashSet.h>
 
 #if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
 
@@ -36,11 +35,16 @@
 
 const float kMotionUpdateInterval = 1.0f / 60.0f;
 
-@interface WebCoreMotionManager : NSObject {
+namespace WebCore {
+class DeviceMotionClientIOS;
+class MotionManagerClient;
+};
+
+WEBCORE_EXPORT @interface WebCoreMotionManager : NSObject {
     CMMotionManager* m_motionManager;
     CLLocationManager* m_locationManager;
     HashSet<WebCore::DeviceMotionClientIOS*> m_deviceMotionClients;
-    HashSet<WebCore::DeviceOrientationClientIOS*> m_deviceOrientationClients;
+    WeakHashSet<WebCore::MotionManagerClient> m_deviceOrientationClients;
     NSTimer* m_updateTimer;
     BOOL m_gyroAvailable;
     BOOL m_headingAvailable;
@@ -50,8 +54,8 @@
 + (WebCoreMotionManager *)sharedManager;
 - (void)addMotionClient:(WebCore::DeviceMotionClientIOS *)client;
 - (void)removeMotionClient:(WebCore::DeviceMotionClientIOS *)client;
-- (void)addOrientationClient:(WebCore::DeviceOrientationClientIOS *)client;
-- (void)removeOrientationClient:(WebCore::DeviceOrientationClientIOS *)client;
+- (void)addOrientationClient:(WebCore::MotionManagerClient *)client;
+- (void)removeOrientationClient:(WebCore::MotionManagerClient *)client;
 - (BOOL)gyroAvailable;
 - (BOOL)headingAvailable;
 @end
diff --git a/Source/WebCore/platform/ios/WebCoreMotionManager.mm b/Source/WebCore/platform/ios/WebCoreMotionManager.mm
index 8f0a86d..0f23352 100644
--- a/Source/WebCore/platform/ios/WebCoreMotionManager.mm
+++ b/Source/WebCore/platform/ios/WebCoreMotionManager.mm
@@ -28,6 +28,8 @@
 
 #if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
 
+#import "DeviceMotionClientIOS.h"
+#import "MotionManagerClient.h"
 #import "WebCoreObjCExtras.h"
 #import "WebCoreThreadRun.h"
 #import <CoreLocation/CoreLocation.h>
@@ -112,16 +114,16 @@
         [self checkClientStatus];
 }
 
-- (void)addOrientationClient:(WebCore::DeviceOrientationClientIOS *)client
+- (void)addOrientationClient:(WebCore::MotionManagerClient *)client
 {
-    m_deviceOrientationClients.add(client);
+    m_deviceOrientationClients.add(*client);
     if (m_initialized)
         [self checkClientStatus];
 }
 
-- (void)removeOrientationClient:(WebCore::DeviceOrientationClientIOS *)client
+- (void)removeOrientationClient:(WebCore::MotionManagerClient *)client
 {
-    m_deviceOrientationClients.remove(client);
+    m_deviceOrientationClients.remove(*client);
     if (m_initialized)
         [self checkClientStatus];
 }
@@ -169,7 +171,7 @@
     // be no chance that m_motionManager has not been created.
     ASSERT(m_motionManager);
 
-    if (m_deviceMotionClients.size() || m_deviceOrientationClients.size()) {
+    if (m_deviceMotionClients.size() || m_deviceOrientationClients.computeSize()) {
         if (m_gyroAvailable)
             [m_motionManager startDeviceMotionUpdates];
         else
@@ -246,8 +248,11 @@
 
         CMAttitude* attitude = newMotion.attitude;
 
-        auto orientationClients = copyToVector(m_deviceOrientationClients);
-
+        Vector<WeakPtr<MotionManagerClient>> orientationClients;
+        orientationClients.reserveInitialCapacity(m_deviceOrientationClients.computeSize());
+        for (auto& client : m_deviceOrientationClients)
+            orientationClients.uncheckedAppend(makeWeakPtr(&client));
+        
         // Compose the raw motion data to an intermediate ZXY-based 3x3 rotation
         // matrix (R) where [z=attitude.yaw, x=attitude.pitch, y=attitude.roll]
         // in the form:
@@ -319,8 +324,10 @@
         double heading = (m_headingAvailable && newHeading) ? newHeading.magneticHeading : 0;
         double headingAccuracy = (m_headingAvailable && newHeading) ? newHeading.headingAccuracy : -1;
 
-        for (size_t i = 0; i < orientationClients.size(); ++i)
-            orientationClients[i]->orientationChanged(alpha, beta, gamma, heading, headingAccuracy);
+        for (size_t i = 0; i < orientationClients.size(); ++i) {
+            if (orientationClients[i])
+                orientationClients[i]->orientationChanged(alpha, beta, gamma, heading, headingAccuracy);
+        }
     });
 }
 
diff --git a/Source/WebKit/ChangeLog b/Source/WebKit/ChangeLog
index 5df1f83..702b830 100644
--- a/Source/WebKit/ChangeLog
+++ b/Source/WebKit/ChangeLog
@@ -1,3 +1,25 @@
+2019-12-06  Per Arne Vollan  <pvollan@apple.com>
+
+        [iOS] Calls to device orientation API should be done in the UI process
+        https://bugs.webkit.org/show_bug.cgi?id=204720
+
+        Reviewed by Alex Christensen.
+
+        Add a new class, WebDeviceOrientationUpdateProviderProxy, to handle messages to start and stop updating device orientation
+        in the UI process. Also, add a message to update the device orientation in the WebContent process. In the UI process, the
+        device orientation API is called through the already existing WebCoreMotionManager class.
+
+        * DerivedSources-input.xcfilelist:
+        * DerivedSources-output.xcfilelist:
+        * DerivedSources.make:
+        * UIProcess/WebPageProxy.cpp:
+        (WebKit::m_webDeviceOrientationUpdateProviderProxy):
+        (WebKit::m_resetRecentCrashCountTimer): Deleted.
+        * UIProcess/WebPageProxy.h:
+        * WebKit.xcodeproj/project.pbxproj:
+        * WebProcess/WebPage/WebPage.cpp:
+        (WebKit::m_overriddenMediaType):
+
 2019-12-06  Chris Dumez  <cdumez@apple.com>
 
         Reduce timeout for page to handle beforeunload events when trying to close a page
diff --git a/Source/WebKit/DerivedSources-input.xcfilelist b/Source/WebKit/DerivedSources-input.xcfilelist
index cafcd9b..7f08f2b 100644
--- a/Source/WebKit/DerivedSources-input.xcfilelist
+++ b/Source/WebKit/DerivedSources-input.xcfilelist
@@ -88,6 +88,7 @@
 $(PROJECT_DIR)/UIProcess/WebProcessProxy.messages.in
 $(PROJECT_DIR)/UIProcess/ios/EditableImageController.messages.in
 $(PROJECT_DIR)/UIProcess/ios/SmartMagnificationController.messages.in
+$(PROJECT_DIR)/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.messages.in
 $(PROJECT_DIR)/UIProcess/mac/SecItemShimProxy.messages.in
 $(PROJECT_DIR)/WebProcess/ApplePay/WebPaymentCoordinator.messages.in
 $(PROJECT_DIR)/WebProcess/Automation/WebAutomationSessionProxy.js
@@ -113,6 +114,7 @@
 $(PROJECT_DIR)/WebProcess/Storage/WebSWContextManagerConnection.messages.in
 $(PROJECT_DIR)/WebProcess/UserContent/WebUserContentController.messages.in
 $(PROJECT_DIR)/WebProcess/WebAuthentication/WebAuthenticatorCoordinator.messages.in
+$(PROJECT_DIR)/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.messages.in
 $(PROJECT_DIR)/WebProcess/WebPage/Cocoa/TextCheckingControllerProxy.messages.in
 $(PROJECT_DIR)/WebProcess/WebPage/DrawingArea.messages.in
 $(PROJECT_DIR)/WebProcess/WebPage/EventDispatcher.messages.in
diff --git a/Source/WebKit/DerivedSources-output.xcfilelist b/Source/WebKit/DerivedSources-output.xcfilelist
index 1b5bbee..3b1e941 100644
--- a/Source/WebKit/DerivedSources-output.xcfilelist
+++ b/Source/WebKit/DerivedSources-output.xcfilelist
@@ -193,6 +193,12 @@
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebCookieManagerProxyMessageReceiver.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebCookieManagerProxyMessages.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebCookieManagerProxyMessagesReplies.h
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderMessageReceiver.cpp
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderMessages.h
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderMessagesReplies.h
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderProxyMessageReceiver.cpp
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderProxyMessages.h
+$(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderProxyMessagesReplies.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebFullScreenManagerMessageReceiver.cpp
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebFullScreenManagerMessages.h
 $(BUILT_PRODUCTS_DIR)/DerivedSources/WebKit2/WebFullScreenManagerMessagesReplies.h
diff --git a/Source/WebKit/DerivedSources.make b/Source/WebKit/DerivedSources.make
index 493afc9..be525e1 100644
--- a/Source/WebKit/DerivedSources.make
+++ b/Source/WebKit/DerivedSources.make
@@ -189,6 +189,8 @@
     WebSWContextManagerConnection \
     WebSWServerConnection \
     WebSWServerToContextConnection \
+    WebDeviceOrientationUpdateProvider \
+    WebDeviceOrientationUpdateProviderProxy \
     WebSocketChannel \
     WebSocketStream \
     WebUserContentController \
diff --git a/Source/WebKit/UIProcess/WebPageProxy.cpp b/Source/WebKit/UIProcess/WebPageProxy.cpp
index d841d3d..c5f6eb3 100644
--- a/Source/WebKit/UIProcess/WebPageProxy.cpp
+++ b/Source/WebKit/UIProcess/WebPageProxy.cpp
@@ -451,6 +451,9 @@
 #endif
     , m_resetRecentCrashCountTimer(RunLoop::main(), this, &WebPageProxy::resetRecentCrashCount)
     , m_tryCloseTimeoutTimer(RunLoop::main(), this, &WebPageProxy::tryCloseTimedOut)
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+    , m_webDeviceOrientationUpdateProviderProxy(*this)
+#endif
 {
     RELEASE_LOG_IF_ALLOWED(Loading, "constructor:");
 
diff --git a/Source/WebKit/UIProcess/WebPageProxy.h b/Source/WebKit/UIProcess/WebPageProxy.h
index ed83bbf..4d26a19 100644
--- a/Source/WebKit/UIProcess/WebPageProxy.h
+++ b/Source/WebKit/UIProcess/WebPageProxy.h
@@ -149,6 +149,10 @@
 #include "SOAuthorizationLoadPolicy.h"
 #endif
 
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+#include "WebDeviceOrientationUpdateProviderProxy.h"
+#endif
+
 #if ENABLE(MEDIA_SESSION)
 namespace WebCore {
 class MediaSessionMetadata;
@@ -2632,6 +2636,10 @@
     bool m_isQuotaIncreaseDenied { false };
     
     String m_overriddenMediaType;
+        
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+    WebDeviceOrientationUpdateProviderProxy m_webDeviceOrientationUpdateProviderProxy;
+#endif
 };
 
 } // namespace WebKit
diff --git a/Source/WebKit/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.h b/Source/WebKit/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.h
new file mode 100644
index 0000000..af56d7c
--- /dev/null
+++ b/Source/WebKit/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2019 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+
+#include "MessageReceiver.h"
+#include <WebCore/MotionManagerClient.h>
+
+namespace WebKit {
+
+class WebPageProxy;
+
+class WebDeviceOrientationUpdateProviderProxy : public WebCore::MotionManagerClient, private IPC::MessageReceiver {
+public:
+    WebDeviceOrientationUpdateProviderProxy(WebPageProxy&);
+    ~WebDeviceOrientationUpdateProviderProxy();
+
+    void startUpdatingDeviceOrientation();
+    void stopUpdatingDeviceOrientation();
+    
+private:
+    // WebCore::WebCoreMotionManagerClient
+    void orientationChanged(double, double, double, double, double) final;
+    
+    // IPC::MessageReceiver.
+    void didReceiveMessage(IPC::Connection&, IPC::Decoder&) override;
+
+    WebPageProxy& m_page;
+};
+
+} // namespace WebKit
+
+#endif // PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
diff --git a/Source/WebKit/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.messages.in b/Source/WebKit/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.messages.in
new file mode 100644
index 0000000..d3af92d
--- /dev/null
+++ b/Source/WebKit/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.messages.in
@@ -0,0 +1,28 @@
+# Copyright (C) 2019 Apple Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1.  Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+# 2.  Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+messages -> WebDeviceOrientationUpdateProviderProxy NotRefCounted {
+    StartUpdatingDeviceOrientation();
+    StopUpdatingDeviceOrientation();
+}
+#endif
diff --git a/Source/WebKit/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.mm b/Source/WebKit/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.mm
new file mode 100644
index 0000000..76a121b
--- /dev/null
+++ b/Source/WebKit/UIProcess/ios/WebDeviceOrientationUpdateProviderProxy.mm
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2019 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#import "config.h"
+#import "WebDeviceOrientationUpdateProviderProxy.h"
+
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+
+#import "WebDeviceOrientationUpdateProviderMessages.h"
+#import "WebDeviceOrientationUpdateProviderProxyMessages.h"
+#import "WebPageProxy.h"
+#import "WebProcessProxy.h"
+#import <WebCore/WebCoreMotionManager.h>
+
+namespace WebKit {
+
+WebDeviceOrientationUpdateProviderProxy::WebDeviceOrientationUpdateProviderProxy(WebPageProxy& page)
+    : m_page(page)
+{
+    m_page.process().addMessageReceiver(Messages::WebDeviceOrientationUpdateProviderProxy::messageReceiverName(), m_page.webPageID(), *this);
+}
+
+WebDeviceOrientationUpdateProviderProxy::~WebDeviceOrientationUpdateProviderProxy()
+{
+    m_page.process().removeMessageReceiver(Messages::WebDeviceOrientationUpdateProviderProxy::messageReceiverName(), m_page.webPageID());
+}
+
+void WebDeviceOrientationUpdateProviderProxy::startUpdatingDeviceOrientation()
+{
+    [[WebCoreMotionManager sharedManager] addOrientationClient:this];
+}
+
+void WebDeviceOrientationUpdateProviderProxy::stopUpdatingDeviceOrientation()
+{
+    [[WebCoreMotionManager sharedManager] removeOrientationClient:this];
+}
+
+void WebDeviceOrientationUpdateProviderProxy::orientationChanged(double alpha, double beta, double gamma, double compassHeading, double compassAccuracy)
+{
+    m_page.send(Messages::WebDeviceOrientationUpdateProvider::DeviceOrientationChanged(alpha, beta, gamma, compassHeading, compassAccuracy));
+}
+
+} // namespace WebKit
+
+#endif // PLATFORM(IOS_FAMILY)
diff --git a/Source/WebKit/WebKit.xcodeproj/project.pbxproj b/Source/WebKit/WebKit.xcodeproj/project.pbxproj
index 95ce08d..f79ddc1 100644
--- a/Source/WebKit/WebKit.xcodeproj/project.pbxproj
+++ b/Source/WebKit/WebKit.xcodeproj/project.pbxproj
@@ -1696,6 +1696,14 @@
 		E1D26A53175964D90095BFD1 /* WebContentProcess.xib in Resources */ = {isa = PBXBuildFile; fileRef = E1D26A4C1759634E0095BFD1 /* WebContentProcess.xib */; };
 		E1E552C516AE065F004ED653 /* SandboxInitializationParameters.h in Headers */ = {isa = PBXBuildFile; fileRef = E1E552C316AE065E004ED653 /* SandboxInitializationParameters.h */; };
 		E1EE53E311F8CFC000CCBEE4 /* InjectedBundlePageEditorClient.h in Headers */ = {isa = PBXBuildFile; fileRef = E1EE53DC11F8CF9F00CCBEE4 /* InjectedBundlePageEditorClient.h */; };
+		E3866AE52397400400F88FE9 /* WebDeviceOrientationUpdateProviderProxy.mm in Sources */ = {isa = PBXBuildFile; fileRef = E3866AE42397400400F88FE9 /* WebDeviceOrientationUpdateProviderProxy.mm */; };
+		E3866AE72397405300F88FE9 /* WebDeviceOrientationUpdateProviderProxy.h in Headers */ = {isa = PBXBuildFile; fileRef = E3866AE62397405300F88FE9 /* WebDeviceOrientationUpdateProviderProxy.h */; };
+		E3866B082399A2D100F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessages.h in Headers */ = {isa = PBXBuildFile; fileRef = E3866B052399979C00F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessages.h */; };
+		E3866B092399A2D500F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessageReceiver.cpp in Sources */ = {isa = PBXBuildFile; fileRef = E3866B042399979C00F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessageReceiver.cpp */; };
+		E3866B0A2399A2D900F88FE9 /* WebDeviceOrientationUpdateProviderMessages.h in Headers */ = {isa = PBXBuildFile; fileRef = E3866B072399979D00F88FE9 /* WebDeviceOrientationUpdateProviderMessages.h */; };
+		E3866B0B2399A2DD00F88FE9 /* WebDeviceOrientationUpdateProviderMessageReceiver.cpp in Sources */ = {isa = PBXBuildFile; fileRef = E3866B062399979C00F88FE9 /* WebDeviceOrientationUpdateProviderMessageReceiver.cpp */; };
+		E39628DD23960CC600658ECD /* WebDeviceOrientationUpdateProvider.h in Headers */ = {isa = PBXBuildFile; fileRef = E39628DB23960CC500658ECD /* WebDeviceOrientationUpdateProvider.h */; };
+		E39628DE23960CC600658ECD /* WebDeviceOrientationUpdateProvider.cpp in Sources */ = {isa = PBXBuildFile; fileRef = E39628DC23960CC600658ECD /* WebDeviceOrientationUpdateProvider.cpp */; };
 		E413F59D1AC1ADC400345360 /* NetworkCacheEntry.h in Headers */ = {isa = PBXBuildFile; fileRef = E413F59B1AC1ADB600345360 /* NetworkCacheEntry.h */; };
 		E42E06101AA7523B00B11699 /* NetworkCacheIOChannel.h in Headers */ = {isa = PBXBuildFile; fileRef = E42E060B1AA7440D00B11699 /* NetworkCacheIOChannel.h */; };
 		E42E06121AA75ABD00B11699 /* NetworkCacheData.h in Headers */ = {isa = PBXBuildFile; fileRef = E42E06111AA75ABD00B11699 /* NetworkCacheData.h */; };
@@ -1975,9 +1983,9 @@
 			dstPath = "$(INSTALL_PATH)";
 			dstSubfolderSpec = 0;
 			files = (
+				2DB96053239886C100102791 /* com.apple.WebKit.GPU.sb in CopyFiles */,
 				A78CCDDB193AC9F8005ECC25 /* com.apple.WebKit.Networking.sb in CopyFiles */,
 				A78CCDDC193AC9FB005ECC25 /* com.apple.WebKit.WebContent.sb in CopyFiles */,
-				2DB96053239886C100102791 /* com.apple.WebKit.GPU.sb in CopyFiles */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -4806,6 +4814,16 @@
 		E1EE53DC11F8CF9F00CCBEE4 /* InjectedBundlePageEditorClient.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = InjectedBundlePageEditorClient.h; sourceTree = "<group>"; };
 		E1EE53E611F8CFFB00CCBEE4 /* InjectedBundlePageEditorClient.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = InjectedBundlePageEditorClient.cpp; sourceTree = "<group>"; };
 		E3439B632345463A0011DE0B /* NetworkProcessConnectionInfo.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = NetworkProcessConnectionInfo.h; path = Network/NetworkProcessConnectionInfo.h; sourceTree = "<group>"; };
+		E3866AE42397400400F88FE9 /* WebDeviceOrientationUpdateProviderProxy.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; name = WebDeviceOrientationUpdateProviderProxy.mm; path = ios/WebDeviceOrientationUpdateProviderProxy.mm; sourceTree = "<group>"; };
+		E3866AE62397405300F88FE9 /* WebDeviceOrientationUpdateProviderProxy.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = WebDeviceOrientationUpdateProviderProxy.h; path = ios/WebDeviceOrientationUpdateProviderProxy.h; sourceTree = "<group>"; };
+		E3866AED2398471A00F88FE9 /* WebDeviceOrientationUpdateProviderProxy.messages.in */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; name = WebDeviceOrientationUpdateProviderProxy.messages.in; path = ios/WebDeviceOrientationUpdateProviderProxy.messages.in; sourceTree = "<group>"; };
+		E3866B042399979C00F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessageReceiver.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = WebDeviceOrientationUpdateProviderProxyMessageReceiver.cpp; path = DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderProxyMessageReceiver.cpp; sourceTree = BUILT_PRODUCTS_DIR; };
+		E3866B052399979C00F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessages.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = WebDeviceOrientationUpdateProviderProxyMessages.h; path = DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderProxyMessages.h; sourceTree = BUILT_PRODUCTS_DIR; };
+		E3866B062399979C00F88FE9 /* WebDeviceOrientationUpdateProviderMessageReceiver.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = WebDeviceOrientationUpdateProviderMessageReceiver.cpp; path = DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderMessageReceiver.cpp; sourceTree = BUILT_PRODUCTS_DIR; };
+		E3866B072399979D00F88FE9 /* WebDeviceOrientationUpdateProviderMessages.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = WebDeviceOrientationUpdateProviderMessages.h; path = DerivedSources/WebKit2/WebDeviceOrientationUpdateProviderMessages.h; sourceTree = BUILT_PRODUCTS_DIR; };
+		E39628DB23960CC500658ECD /* WebDeviceOrientationUpdateProvider.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = WebDeviceOrientationUpdateProvider.h; sourceTree = "<group>"; };
+		E39628DC23960CC600658ECD /* WebDeviceOrientationUpdateProvider.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = WebDeviceOrientationUpdateProvider.cpp; sourceTree = "<group>"; };
+		E39628E423971F3400658ECD /* WebDeviceOrientationUpdateProvider.messages.in */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = WebDeviceOrientationUpdateProvider.messages.in; sourceTree = "<group>"; };
 		E404907021DE65F70037F0DB /* ScrollerPairMac.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ScrollerPairMac.h; sourceTree = "<group>"; };
 		E404907121DE65F70037F0DB /* ScrollingTreeFrameScrollingNodeRemoteMac.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = ScrollingTreeFrameScrollingNodeRemoteMac.cpp; sourceTree = "<group>"; };
 		E404907221DE65F70037F0DB /* ScrollerPairMac.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ScrollerPairMac.mm; sourceTree = "<group>"; };
@@ -5923,6 +5941,9 @@
 			isa = PBXGroup;
 			children = (
 				2D28F3E01885CCC1004B9EAE /* WebChromeClientIOS.mm */,
+				E39628DC23960CC600658ECD /* WebDeviceOrientationUpdateProvider.cpp */,
+				E39628DB23960CC500658ECD /* WebDeviceOrientationUpdateProvider.h */,
+				E39628E423971F3400658ECD /* WebDeviceOrientationUpdateProvider.messages.in */,
 				2D28F3E21885CCC1004B9EAE /* WebEditorClientIOS.mm */,
 				2D28F3E31885CCC1004B9EAE /* WebFrameLoaderClientIOS.mm */,
 				A1C512C6190656E500448914 /* WebPreviewLoaderClient.cpp */,
@@ -6310,6 +6331,9 @@
 				2DF9593418A42412009785A1 /* ViewGestureControllerIOS.mm */,
 				E5BEF6802130C47F00F31111 /* WebDataListSuggestionsDropdownIOS.h */,
 				E5BEF6812130C47F00F31111 /* WebDataListSuggestionsDropdownIOS.mm */,
+				E3866AE62397405300F88FE9 /* WebDeviceOrientationUpdateProviderProxy.h */,
+				E3866AED2398471A00F88FE9 /* WebDeviceOrientationUpdateProviderProxy.messages.in */,
+				E3866AE42397400400F88FE9 /* WebDeviceOrientationUpdateProviderProxy.mm */,
 				2DA944AB1884E9BA00ED86DB /* WebPageProxyIOS.mm */,
 				2DA944AC1884E9BA00ED86DB /* WebProcessProxyIOS.mm */,
 				0FCB4E3818BBE044000FCFC9 /* WKActionSheet.h */,
@@ -9148,6 +9172,10 @@
 				330934441315B9220097A7BC /* WebCookieManagerMessages.h */,
 				330934451315B9220097A7BC /* WebCookieManagerProxyMessageReceiver.cpp */,
 				330934461315B9220097A7BC /* WebCookieManagerProxyMessages.h */,
+				E3866B062399979C00F88FE9 /* WebDeviceOrientationUpdateProviderMessageReceiver.cpp */,
+				E3866B072399979D00F88FE9 /* WebDeviceOrientationUpdateProviderMessages.h */,
+				E3866B042399979C00F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessageReceiver.cpp */,
+				E3866B052399979C00F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessages.h */,
 				CD73BA48131ACD8E00EEDED2 /* WebFullScreenManagerMessageReceiver.cpp */,
 				CD73BA49131ACD8E00EEDED2 /* WebFullScreenManagerMessages.h */,
 				CD73BA45131ACC8800EEDED2 /* WebFullScreenManagerProxyMessageReceiver.cpp */,
@@ -10135,6 +10163,10 @@
 				E5BEF6822130C48000F31111 /* WebDataListSuggestionsDropdownIOS.h in Headers */,
 				E568B92220A3AC6A00E3C856 /* WebDataListSuggestionsDropdownMac.h in Headers */,
 				46B0524722668D8500265B97 /* WebDeviceOrientationAndMotionAccessController.h in Headers */,
+				E39628DD23960CC600658ECD /* WebDeviceOrientationUpdateProvider.h in Headers */,
+				E3866B0A2399A2D900F88FE9 /* WebDeviceOrientationUpdateProviderMessages.h in Headers */,
+				E3866AE72397405300F88FE9 /* WebDeviceOrientationUpdateProviderProxy.h in Headers */,
+				E3866B082399A2D100F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessages.h in Headers */,
 				CD19A26E1A13E834008D650E /* WebDiagnosticLoggingClient.h in Headers */,
 				1A5B1C5518987EDF004FCF9B /* WebDocumentLoader.h in Headers */,
 				BC032D7B10F4378D0058C15A /* WebDragClient.h in Headers */,
@@ -11828,6 +11860,10 @@
 				330934471315B9220097A7BC /* WebCookieManagerMessageReceiver.cpp in Sources */,
 				330934491315B9220097A7BC /* WebCookieManagerProxyMessageReceiver.cpp in Sources */,
 				2D92A788212B6AB100F493FD /* WebCoreArgumentCoders.cpp in Sources */,
+				E39628DE23960CC600658ECD /* WebDeviceOrientationUpdateProvider.cpp in Sources */,
+				E3866B0B2399A2DD00F88FE9 /* WebDeviceOrientationUpdateProviderMessageReceiver.cpp in Sources */,
+				E3866AE52397400400F88FE9 /* WebDeviceOrientationUpdateProviderProxy.mm in Sources */,
+				E3866B092399A2D500F88FE9 /* WebDeviceOrientationUpdateProviderProxyMessageReceiver.cpp in Sources */,
 				2D92A789212B6AB100F493FD /* WebEvent.cpp in Sources */,
 				CD73BA4E131ACDB700EEDED2 /* WebFullScreenManagerMessageReceiver.cpp in Sources */,
 				CD73BA47131ACC9A00EEDED2 /* WebFullScreenManagerProxyMessageReceiver.cpp in Sources */,
diff --git a/Source/WebKit/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.cpp b/Source/WebKit/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.cpp
new file mode 100644
index 0000000..59d69c3
--- /dev/null
+++ b/Source/WebKit/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.cpp
@@ -0,0 +1,75 @@
+/*
+* Copyright (C) 2019 Apple Inc. All rights reserved.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions
+* are met:
+* 1. Redistributions of source code must retain the above copyright
+*    notice, this list of conditions and the following disclaimer.
+* 2. Redistributions in binary form must reproduce the above copyright
+*    notice, this list of conditions and the following disclaimer in the
+*    documentation and/or other materials provided with the distribution.
+*
+* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+* THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include "config.h"
+#include "WebDeviceOrientationUpdateProvider.h"
+
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+
+#include "WebDeviceOrientationUpdateProviderMessages.h"
+#include "WebDeviceOrientationUpdateProviderProxyMessages.h"
+#include "WebPage.h"
+#include "WebProcess.h"
+
+#include <WebCore/MotionManagerClient.h>
+
+namespace WebKit {
+
+WebDeviceOrientationUpdateProvider::WebDeviceOrientationUpdateProvider(WebPage& page)
+    : m_page(makeWeakPtr(page))
+{
+    WebProcess::singleton().addMessageReceiver(Messages::WebDeviceOrientationUpdateProvider::messageReceiverName(), page.identifier(), *this);
+}
+
+WebDeviceOrientationUpdateProvider::~WebDeviceOrientationUpdateProvider()
+{
+    WebProcess::singleton().removeMessageReceiver(Messages::WebDeviceOrientationUpdateProvider::messageReceiverName());
+}
+
+void WebDeviceOrientationUpdateProvider::startUpdating(WebCore::MotionManagerClient& client)
+{
+    if (m_clients.isEmpty() && m_page)
+        m_page->send(Messages::WebDeviceOrientationUpdateProviderProxy::StartUpdatingDeviceOrientation());
+    m_clients.add(&client);
+}
+
+void WebDeviceOrientationUpdateProvider::stopUpdating(WebCore::MotionManagerClient& client)
+{
+    if (m_clients.isEmpty())
+        return;
+    m_clients.remove(&client);
+    if (m_clients.isEmpty() && m_page)
+        m_page->send(Messages::WebDeviceOrientationUpdateProviderProxy::StopUpdatingDeviceOrientation());
+}
+
+void WebDeviceOrientationUpdateProvider::deviceOrientationChanged(double alpha, double beta, double gamma, double compassHeading, double compassAccuracy)
+{
+    for (auto* client : copyToVector(m_clients))
+        client->orientationChanged(alpha, beta, gamma, compassHeading, compassAccuracy);
+}
+
+}
+
+#endif // PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
diff --git a/Source/WebKit/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.h b/Source/WebKit/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.h
new file mode 100644
index 0000000..cadef47
--- /dev/null
+++ b/Source/WebKit/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.h
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2019 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include "MessageReceiver.h"
+#include "WebPage.h"
+
+#include <WebCore/DeviceOrientationUpdateProvider.h>
+
+#include <wtf/HashSet.h>
+#include <wtf/WeakPtr.h>
+
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+
+namespace WebKit {
+
+class WebDeviceOrientationUpdateProvider final : public WebCore::DeviceOrientationUpdateProvider, private IPC::MessageReceiver {
+public:
+    static Ref<WebDeviceOrientationUpdateProvider> create(WebPage& page) { return adoptRef(*new WebDeviceOrientationUpdateProvider(page));}
+
+private:
+    WebDeviceOrientationUpdateProvider(WebPage&);
+    ~WebDeviceOrientationUpdateProvider();
+
+    // WebCore::DeviceOrientationUpdateProvider
+    void startUpdating(WebCore::MotionManagerClient&) final;
+    void stopUpdating(WebCore::MotionManagerClient&) final;
+    void deviceOrientationChanged(double, double, double, double, double) final;
+
+    // IPC::MessageReceiver.
+    void didReceiveMessage(IPC::Connection&, IPC::Decoder&) override;
+
+    WeakPtr<WebPage> m_page;
+    HashSet<WebCore::MotionManagerClient*> m_clients;
+};
+
+}
+
+#endif // PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
diff --git a/Source/WebKit/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.messages.in b/Source/WebKit/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.messages.in
new file mode 100644
index 0000000..c43ad8c
--- /dev/null
+++ b/Source/WebKit/WebProcess/WebCoreSupport/WebDeviceOrientationUpdateProvider.messages.in
@@ -0,0 +1,27 @@
+# Copyright (C) 2019 Apple Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1.  Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+# 2.  Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR
+# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+messages -> WebDeviceOrientationUpdateProvider {
+    DeviceOrientationChanged(double alpha, double beta, double gamma, double compassHeading, double compassAccuracy)
+}
+#endif
diff --git a/Source/WebKit/WebProcess/WebPage/WebPage.cpp b/Source/WebKit/WebProcess/WebPage/WebPage.cpp
index e940ba3..2bf24f3 100644
--- a/Source/WebKit/WebProcess/WebPage/WebPage.cpp
+++ b/Source/WebKit/WebProcess/WebPage/WebPage.cpp
@@ -307,6 +307,10 @@
 #include <WebCore/AuthenticatorCoordinator.h>
 #endif
 
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+#include "WebDeviceOrientationUpdateProvider.h"
+#endif
+
 namespace WebKit {
 using namespace JSC;
 using namespace WebCore;
@@ -501,6 +505,10 @@
 #if ENABLE(APPLICATION_MANIFEST)
     pageConfiguration.applicationManifest = parameters.applicationManifest;
 #endif
+    
+#if PLATFORM(IOS_FAMILY) && ENABLE(DEVICE_ORIENTATION)
+    pageConfiguration.deviceOrientationUpdateProvider = WebDeviceOrientationUpdateProvider::create(*this);
+#endif
 
     m_page = makeUnique<Page>(WTFMove(pageConfiguration));