Suppress JavaScript dialogs when a tab puts itself into fullscreen.

chrome/browser/ui/browser.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 CHROME_BROWSER_UI_BROWSER_H_
 #define CHROME_BROWSER_UI_BROWSER_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 439 matching lines @@
   void TabReplacedAt(TabStripModel* tab_strip_model,
                      content::WebContents* old_contents,
                      content::WebContents* new_contents,
                      int index) override;
   void TabPinnedStateChanged(content::WebContents* contents,
                              int index) override;
   void TabStripEmpty() override;
 
   // Overridden from content::WebContentsDelegate:
   bool CanOverscrollContent() const override;
+  bool ShouldSuppressDialogs(content::WebContents* source,
+                             bool before_unload) override;
   bool ShouldPreserveAbortedURLs(content::WebContents* source) override;
   void SetFocusToLocationBar(bool select_all) override;
   bool PreHandleKeyboardEvent(content::WebContents* source,
                               const content::NativeWebKeyboardEvent& event,
                               bool* is_keyboard_shortcut) override;
   void HandleKeyboardEvent(
       content::WebContents* source,
       const content::NativeWebKeyboardEvent& event) override;
   void ShowValidationMessage(content::WebContents* web_contents,
                              const gfx::Rect& anchor_in_root_view,
@@ skipping 539 matching lines @@
   // The following factory is used for chrome update coalescing.
   base::WeakPtrFactory<Browser> chrome_updater_factory_;
 
   // The following factory is used to close the frame at a later time.
   base::WeakPtrFactory<Browser> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Browser);
 };
 
 #endif  // CHROME_BROWSER_UI_BROWSER_H_