Suppress JavaScript dialogs when a tab puts itself into fullscreen.

extensions/browser/app_window/app_window.h

 // Copyright 2014 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 EXTENSIONS_BROWSER_APP_WINDOW_APP_WINDOW_H_
 #define EXTENSIONS_BROWSER_APP_WINDOW_APP_WINDOW_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 371 matching lines @@
 
  protected:
   ~AppWindow() override;
 
  private:
   // PlatformAppBrowserTest needs access to web_contents()
   friend class PlatformAppBrowserTest;
 
   // content::WebContentsDelegate implementation.
   void CloseContents(content::WebContents* contents) override;
-  bool ShouldSuppressDialogs(content::WebContents* source) override;
+  bool ShouldSuppressDialogs(content::WebContents* source,
+                             bool before_unload) override;
   content::ColorChooser* OpenColorChooser(
       content::WebContents* web_contents,
       SkColor color,
       const std::vector<content::ColorSuggestion>& suggestions) override;
   void RunFileChooser(content::RenderFrameHost* render_frame_host,
                       const content::FileChooserParams& params) override;
   bool IsPopupOrPanel(const content::WebContents* source) const override;
   void MoveContents(content::WebContents* source,
                     const gfx::Rect& pos) override;
   void NavigationStateChanged(content::WebContents* source,
@@ skipping 181 matching lines @@
   base::Closure on_first_commit_callback_;
 
   base::WeakPtrFactory<AppWindow> image_loader_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AppWindow);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_APP_WINDOW_APP_WINDOW_H_