Change Element::didAddUserAgentShadowRoot() to take a reference instead of a pointer
https://bugs.webkit.org/show_bug.cgi?id=179153

Reviewed by Ryosuke Niwa.

Element::didAddUserAgentShadowRoot() is always passed a non-null pointer to the added
ShadowRoot. Therefore we should have didAddUserAgentShadowRoot() take a lvalue reference
to a ShadowRoot.

No functionality changed. So, no new tests.

* dom/Element.cpp:
(WebCore::Element::addShadowRoot):
* dom/Element.h:
(WebCore::Element::didAddUserAgentShadowRoot):
* html/HTMLDetailsElement.cpp:
(WebCore::HTMLDetailsElement::didAddUserAgentShadowRoot):
* html/HTMLDetailsElement.h:
* html/HTMLInputElement.cpp:
(WebCore::HTMLInputElement::didAddUserAgentShadowRoot):
* html/HTMLInputElement.h:
* html/HTMLMediaElement.cpp:
(WebCore::HTMLMediaElement::didAddUserAgentShadowRoot):
* html/HTMLMediaElement.h:
* html/HTMLMeterElement.cpp:
(WebCore::HTMLMeterElement::didAddUserAgentShadowRoot):
* html/HTMLMeterElement.h:
* html/HTMLPlugInElement.cpp:
(WebCore::HTMLPlugInElement::didAddUserAgentShadowRoot):
* html/HTMLPlugInElement.h:
* html/HTMLPlugInImageElement.cpp:
(WebCore::HTMLPlugInImageElement::didAddUserAgentShadowRoot):
* html/HTMLPlugInImageElement.h:
* html/HTMLProgressElement.cpp:
(WebCore::HTMLProgressElement::didAddUserAgentShadowRoot):
* html/HTMLProgressElement.h:
* html/HTMLSummaryElement.cpp:
(WebCore::HTMLSummaryElement::didAddUserAgentShadowRoot):
* html/HTMLSummaryElement.h:
* html/HTMLTextAreaElement.cpp:
(WebCore::HTMLTextAreaElement::didAddUserAgentShadowRoot):
* html/HTMLTextAreaElement.h:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@224316 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/WebCore/html/HTMLSummaryElement.cpp b/Source/WebCore/html/HTMLSummaryElement.cpp
index 7d40091..1271026 100644
--- a/Source/WebCore/html/HTMLSummaryElement.cpp
+++ b/Source/WebCore/html/HTMLSummaryElement.cpp
@@ -65,10 +65,10 @@
     return createRenderer<RenderBlockFlow>(*this, WTFMove(style));
 }
 
-void HTMLSummaryElement::didAddUserAgentShadowRoot(ShadowRoot* root)
+void HTMLSummaryElement::didAddUserAgentShadowRoot(ShadowRoot& root)
 {
-    root->appendChild(DetailsMarkerControl::create(document()));
-    root->appendChild(HTMLSlotElement::create(slotTag, document()));
+    root.appendChild(DetailsMarkerControl::create(document()));
+    root.appendChild(HTMLSlotElement::create(slotTag, document()));
 }
 
 HTMLDetailsElement* HTMLSummaryElement::detailsElement() const