Delete scrollingCoordinatorEnabled setting

The scrollingCoordinatorEnabled setting is redundant with acceleratedCompositingEnabled.

Review URL: https://codereview.chromium.org/329863002

git-svn-id: svn://svn.chromium.org/blink/trunk@175999 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/core/frame/Settings.in

@@ -123,7 +123,6 @@ allowConnectingInsecureWebSocket initial=false
 mediaControlsOverlayPlayButtonEnabled initial=false
 mediaPlaybackRequiresUserGesture initial=false
 
-scrollingCoordinatorEnabled initial=false
 scrollAnimatorEnabled initial=true
 
 shouldRespectImageOrientation initial=false

third_party/WebKit/Source/core/page/Page.cpp

@@ -166,7 +166,7 @@ ViewportDescription Page::viewportDescription() const
 
 ScrollingCoordinator* Page::scrollingCoordinator()
 {
-    if (!m_scrollingCoordinator && m_settings->scrollingCoordinatorEnabled())
+    if (!m_scrollingCoordinator && m_settings->acceleratedCompositingEnabled())
         m_scrollingCoordinator = ScrollingCoordinator::create(this);
 
     return m_scrollingCoordinator.get();

third_party/WebKit/Source/web/WebSettingsImpl.cpp

@@ -428,7 +428,6 @@ void WebSettingsImpl::setEditingBehavior(EditingBehavior behavior)
 void WebSettingsImpl::setAcceleratedCompositingEnabled(bool enabled)
 {
     m_settings->setAcceleratedCompositingEnabled(enabled);
-    m_settings->setScrollingCoordinatorEnabled(enabled);
 }
 
 void WebSettingsImpl::setMockScrollbarsEnabled(bool enabled)