Refactor overlay fullscreen video handling into a single callback

third_party/WebKit/Source/web/FullscreenController.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 29 matching lines @@
 
 class Element;
 class LocalFrame;
 class WebViewImpl;
 
 class FullscreenController final
     : public GarbageCollected<FullscreenController> {
  public:
   static FullscreenController* create(WebViewImpl*);
 
+  // Called by Fullscreen (via ChromeClient) to request entering or exiting
+  // fullscreen.
+  void enterFullscreenForElement(Element*);
+  void exitFullscreen(LocalFrame*);
+
+  // Called by content::RenderWidget (via WebWidget) to notify that we've
+  // entered or exited fullscreen. This can be because we requested it, or it
+  // can be initiated by the browser directly.
   void didEnterFullscreen();
   void didExitFullscreen();
 
-  void enterFullscreenForElement(Element*);
-  void exitFullscreen(LocalFrame*);
+  // Called by Fullscreen (via ChromeClient) to notify that the fullscreen
+  // element has changed.
+  void fullscreenElementChanged(Element*, Element*);
 
   bool isFullscreen() { return m_fullscreenFrame; }
 
   void updateSize();
 
   void didUpdateLayout();
 
   DECLARE_TRACE();
 
  protected:
@@ skipping 15 matching lines @@
 
   // If set, the WebView is in fullscreen mode for an element in this frame.
   Member<LocalFrame> m_fullscreenFrame;
 
   bool m_isCancelingFullscreen;
 };
 
 }  // namespace blink
 
 #endif