Convert Settings::rootLayerScrolls to RuntimeEnabledFeatures

third_party/WebKit/Source/core/testing/DummyPageHolder.h

 /*
  * Copyright (c) 2013, Google 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
@@ skipping 31 matching lines @@
 namespace blink {
 
 class Document;
 class LocalFrame;
 class FrameView;
 class IntSize;
 class Settings;
 
 typedef void (*FrameSettingOverrideFunction)(Settings&);
 
-extern void RootLayerScrollsFrameSettingOverride(Settings&);
-
 // Creates a dummy Page, LocalFrame, and FrameView whose clients are all no-op.
 //
 // This class can be used when you write unit tests for components which do not work correctly without layoutObjects.
 // To make sure the layoutObjects are created, you need to call |frameView().layout()| after you add nodes into
 // |document()|.
 //
 // Since DummyPageHolder stores empty clients in it, it must outlive the Page, LocalFrame, FrameView and any other objects
 // created by it. DummyPageHolder's destructor ensures this condition by checking remaining references to the LocalFrame.
 
 class DummyPageHolder {
@@ skipping 17 matching lines @@
 
     Persistent<Page> m_page;
     Persistent<LocalFrame> m_frame;
 
     Persistent<FrameLoaderClient> m_frameLoaderClient;
 };
 
 } // namespace blink
 
 #endif // DummyPageHolder_h