Ignore JavaScript messages (alert/confirm/prompt) during unload handlers.

chrome/browser/prerender/prerender_contents.h

 // Copyright (c) 2011 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 CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 93 matching lines @@
                            const ViewHostMsg_FrameNavigate_Params& params);
   virtual void UpdateTitle(RenderViewHost* render_view_host,
                            int32 page_id,
                            const std::wstring& title);
   virtual WebPreferences GetWebkitPrefs();
   virtual void ProcessWebUIMessage(const ViewHostMsg_DomMessage_Params& params);
   virtual void RunJavaScriptMessage(const std::wstring& message,
                                     const std::wstring& default_prompt,
                                     const GURL& frame_url,
                                     const int flags,
+                                    const bool unload_handler_being_run,
                                     IPC::Message* reply_msg,
                                     bool* did_suppress_message);
   virtual void Close(RenderViewHost* render_view_host);
   virtual void DidStopLoading();
   virtual RendererPreferences GetRendererPrefs(Profile* profile) const;
 
   // RenderViewHostDelegate::View
   virtual void CreateNewWindow(
       int route_id,
       const ViewHostMsg_CreateWindow_Params& params);
@@ skipping 141 matching lines @@
   // Maximum amount of private memory that may be used per PrerenderContents,
   // in MB.
   static const int kMaxPrerenderPrivateMB = 100;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderContents);
 };
 
 }  // prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_