Add WasShown/WasHidden to RenderFrameObserver.

content/renderer/render_widget.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_RENDERER_RENDER_WIDGET_H_
 #define CONTENT_RENDERER_RENDER_WIDGET_H_
 
 #include <deque>
 #include <map>
 
@@ skipping 95 matching lines @@
   ui::MenuSourceType context_menu_source_type() {
     return context_menu_source_type_; }
   gfx::Point touch_editing_context_menu_location() {
     return touch_editing_context_menu_location_;
   }
 
   // Functions to track out-of-process frames for special notifications.
   void RegisterSwappedOutChildFrame(RenderFrameImpl* frame);
   void UnregisterSwappedOutChildFrame(RenderFrameImpl* frame);
 
+  // Functions to track all RenderFrame objects associated with this
+  // RenderWidget.
+  void RegisterRenderFrame(RenderFrameImpl* frame);
+  void UnregisterRenderFrame(RenderFrameImpl* frame);
+
 #if defined(VIDEO_HOLE)
   void RegisterVideoHoleFrame(RenderFrameImpl* frame);
   void UnregisterVideoHoleFrame(RenderFrameImpl* frame);
 #endif  // defined(VIDEO_HOLE)
 
   // IPC::Listener
   virtual bool OnMessageReceived(const IPC::Message& msg) OVERRIDE;
 
   // IPC::Sender
   virtual bool Send(IPC::Message* msg) OVERRIDE;
@@ skipping 587 matching lines @@
 
   scoped_ptr<ResizingModeSelector> resizing_mode_selector_;
 
   // Lists of swapped out RenderFrames that need to be notified
   // of compositing-related events (e.g. DidCommitCompositorFrame).
   ObserverList<RenderFrameImpl> swapped_out_frames_;
 #if defined(VIDEO_HOLE)
   ObserverList<RenderFrameImpl> video_hole_frames_;
 #endif  // defined(VIDEO_HOLE)
 
+  // A list of RenderFrames associated with this RenderWidget. Notifications
+  // are sent to each frame in the list for events such as changing
+  // visibility state for example.
+  ObserverList<RenderFrameImpl> render_frames_;
+
   ui::MenuSourceType context_menu_source_type_;
   gfx::Point touch_editing_context_menu_location_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidget);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_WIDGET_H_