Reland the patch to fix the problem that sometimes panel on Windows is not set to top-most.

chrome/browser/ui/panels/panel_browser_view.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_UI_PANELS_PANEL_BROWSER_VIEW_H_
 #define CHROME_BROWSER_UI_PANELS_PANEL_BROWSER_VIEW_H_
 #pragma once
 
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 27 matching lines @@
   // Called from frame view when titlebar receives a mouse event.
   // Return true if the event is handled.
   bool OnTitlebarMousePressed(const gfx::Point& location);
   bool OnTitlebarMouseDragged(const gfx::Point& location);
   bool OnTitlebarMouseReleased();
   bool OnTitlebarMouseCaptureLost();
 
  private:
   friend class NativePanelTestingWin;
   friend class PanelBrowserViewTest;
-  FRIEND_TEST_ALL_PREFIXES(PanelBrowserViewTest, CreatePanel);
-  FRIEND_TEST_ALL_PREFIXES(PanelBrowserViewTest, ShowOrHideSettingsButton);
-  FRIEND_TEST_ALL_PREFIXES(PanelBrowserViewTest, SetBoundsAnimation);
 
   enum MouseDraggingState {
     NO_DRAGGING,
     DRAGGING_STARTED,
     DRAGGING_ENDED
   };
 
   // Overridden from BrowserView:
   virtual void Init() OVERRIDE;
   virtual void Close() OVERRIDE;
@@ skipping 91 matching lines @@
   base::TimeTicks attention_cleared_time_;
 
   // The last view that had focus in the panel. This is saved so that focus can
   // be restored properly when a drag ends.
   views::View* old_focused_view_;
 
   DISALLOW_COPY_AND_ASSIGN(PanelBrowserView);
 };
 
 #endif  // CHROME_BROWSER_UI_PANELS_PANEL_BROWSER_VIEW_H_