[MSE] Add a runtime-setting for the MediaSource constructor.
https://bugs.webkit.org/show_bug.cgi?id=125336

Reviewed by Eric Carlson.

Source/WebCore:

Add a Setting to enable the MediaSource constructor.

* Modules/mediasource/MediaSource.idl:
* page/Settings.in:

Source/WebKit/mac:

Add a private WebPreference which controls the WebCore mediaSourceEnabled setting.

* WebView/WebPreferenceKeysPrivate.h:
* WebView/WebPreferences.mm:
(+[WebPreferences initialize]):
(-[WebPreferences mediaSourceEnabled]):
(-[WebPreferences setMediaSourceEnabled:]):
* WebView/WebPreferencesPrivate.h:
* WebView/WebView.mm:
(-[WebView _preferencesChanged:]):

Source/WebKit2:

Add a private WKPreferences API to control the WebCore mediaSourceEnabled setting.

* Shared/WebPreferencesStore.h:
* UIProcess/API/C/WKPreferences.cpp:
(WKPreferencesSetMediaSourceEnabled):
(WKPreferencesGetMediaSourceEnabled):
* UIProcess/API/C/WKPreferencesPrivate.h:
* WebProcess/WebPage/WebPage.cpp:
(WebKit::WebPage::updatePreferences):

Tools:

Enable MediaSource in DRT and WKTR.

* DumpRenderTree/mac/DumpRenderTree.mm:
(resetWebPreferencesToConsistentValues):
* WebKitTestRunner/TestController.cpp:
(WTR::TestController::resetPreferencesToConsistentValues):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@160261 268f45cc-cd09-0410-ab3c-d52691b4dbfc
16 files changed