Fix scroll restoration when exiting fullscreen mode.

content/public/browser/web_contents_observer.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_PUBLIC_BROWSER_WEB_CONTENTS_OBSERVER_H_
 #define CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_OBSERVER_H_
 
 #include "base/process/kill.h"
 #include "base/process/process_handle.h"
 #include "content/common/content_export.h"
@@ skipping 383 matching lines @@
   // process.
   virtual void DidUpdateFaviconURL(const std::vector<FaviconURL>& candidates) {}
 
   // Invoked when a pepper plugin creates and shows or destroys a fullscreen
   // RenderWidget.
   virtual void DidShowFullscreenWidget(int routing_id) {}
   virtual void DidDestroyFullscreenWidget(int routing_id) {}
 
   // Invoked when the renderer process has toggled the tab into/out of
   // fullscreen mode.
-  virtual void DidToggleFullscreenModeForTab(bool entered_fullscreen) {}
+  virtual void DidToggleFullscreenModeForTab(bool entered_fullscreen,
+                                             bool will_cause_resize) {}
 
   // Invoked when an interstitial page is attached or detached.
   virtual void DidAttachInterstitialPage() {}
   virtual void DidDetachInterstitialPage() {}
 
   // Invoked before a form repost warning is shown.
   virtual void BeforeFormRepostWarningShow() {}
 
   // Invoked when the beforeunload handler fires. The time is from the renderer
   // process.
@@ skipping 59 matching lines @@
   void ResetWebContents();
 
   WebContentsImpl* web_contents_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentsObserver);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_OBSERVER_H_