Add WasShown/WasHidden to RenderFrameObserver.

content/renderer/render_frame_impl.h

 // Copyright 2013 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_FRAME_IMPL_H_
 #define CONTENT_RENDERER_RENDER_FRAME_IMPL_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 105 matching lines @@
   void SetWebFrame(blink::WebLocalFrame* web_frame);
 
   // This method must be called after the frame has been added to the frame
   // tree. It creates all objects that depend on the frame being at its proper
   // spot.
   void Initialize();
 
   // Notification from RenderView.
   virtual void OnStop();
 
+  // Notifications from RenderWidget.
+  void WasHidden();
+  void WasShown();
+
   // Start/Stop loading notifications.
   // TODO(nasko): Those are page-level methods at this time and come from
   // WebViewClient. We should move them to be WebFrameClient calls and put
   // logic in the browser side to balance starts/stops.
   // |to_different_document| will be true unless the load is a fragment
   // navigation, or triggered by history.pushState/replaceState.
   virtual void didStartLoading(bool to_different_document);
   virtual void didStopLoading();
   virtual void didChangeLoadProgress(double load_progress);
 
@@ skipping 458 matching lines @@
   blink::WebUserMediaClient* web_user_media_client_;
 
   base::WeakPtrFactory<RenderFrameImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderFrameImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_FRAME_IMPL_H_