Don't animate the download shelf when entering/exiting 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 350 matching lines @@
   // Indicates whether or not this browser window can be closed, or
   // would be blocked by in-progress downloads.
   // If executing downloads would be cancelled by this window close,
   // then |*num_downloads_blocking| is updated with how many downloads
   // would be canceled if the close continued.
   DownloadClosePreventionType OkToCloseWithInProgressDownloads(
       int* num_downloads_blocking) const;
 
   // External state change handling ////////////////////////////////////////////
 
-  // Invoked when the fullscreen state of the window changes.
-  // BrowserWindow::EnterFullscreen invokes this after the window has become
-  // fullscreen.
+  // BrowserWindow::EnterFullscreen invokes WindowFullscreenStateWillChange at
+  // the beginning of a fullscreen transition, and WindowFullscreenStateChanged
+  // at the end.
+  void WindowFullscreenStateWillChange();
   void WindowFullscreenStateChanged();
 
   // Assorted browser commands ////////////////////////////////////////////////
 
   // NOTE: Within each of the following sections, the IDs are ordered roughly by
   // how they appear in the GUI/menus (left to right, top to bottom, etc.).
 
   // See the description of
   // FullscreenController::ToggleFullscreenModeWithExtension.
   void ToggleFullscreenModeWithExtension(const GURL& extension_url);
@@ skipping 638 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_