Make RootScroller set the outer viewport scroll layer in the compositor

third_party/WebKit/Source/web/WebViewImpl.h

 /*
  * Copyright (C) 2010 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 477 matching lines @@
     WebLayerTreeView* layerTreeView() const { return m_layerTreeView; }
 
     bool matchesHeuristicsForGpuRasterizationForTesting() const { return m_matchesHeuristicsForGpuRasterization; }
 
     void updateTopControlsState(WebTopControlsState constraint, WebTopControlsState current, bool animate) override;
 
     TopControls& topControls();
     // Called anytime top controls layout height or content offset have changed.
     void didUpdateTopControls();
 
+    // Called to update the root scroller layer on the compositor.
+    void didUpdateRootScrollerLayer(WebLayer*);
+
     void forceNextWebGLContextCreationToFail() override;
     void forceNextDrawingBufferCreationToFail() override;
 
     CompositorProxyClient* createCompositorProxyClient();
     IntSize mainFrameSize();
     WebDisplayMode displayMode() const { return m_displayMode; }
 
     PageScaleConstraintsSet& pageScaleConstraintsSet() const;
 
     FloatSize elasticOverscroll() const { return m_elasticOverscroll; }
@@ skipping 251 matching lines @@
     double m_lastFrameTimeMonotonic;
 };
 
 // We have no ways to check if the specified WebView is an instance of
 // WebViewImpl because WebViewImpl is the only implementation of WebView.
 DEFINE_TYPE_CASTS(WebViewImpl, WebView, webView, true, true);
 
 } // namespace blink
 
 #endif