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

chrome/browser/ui/panels/panel_browser_frame_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_FRAME_VIEW_H_
 #define CHROME_BROWSER_UI_PANELS_PANEL_BROWSER_FRAME_VIEW_H_
 #pragma once
 
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 81 matching lines @@
   virtual bool ShouldTabIconViewAnimate() const OVERRIDE;
   virtual SkBitmap GetFaviconForTabIconView() OVERRIDE;
 
   // Overridden from AnimationDelegate:
   virtual void AnimationEnded(const ui::Animation* animation) OVERRIDE;
   virtual void AnimationProgressed(const ui::Animation* animation) OVERRIDE;
   virtual void AnimationCanceled(const ui::Animation* animation) OVERRIDE;
 
  private:
   friend class PanelBrowserViewTest;
-  FRIEND_TEST_ALL_PREFIXES(PanelBrowserViewTest, CreatePanel);
-  FRIEND_TEST_ALL_PREFIXES(PanelBrowserViewTest, ShowOrHideSettingsButton);
 
   enum PaintState {
     NOT_PAINTED,
     PAINT_AS_INACTIVE,
     PAINT_AS_ACTIVE,
     PAINT_FOR_ATTENTION
   };
 
   class MouseWatcher : public MessageLoopForUI::Observer {
    public:
@@ skipping 83 matching lines @@
   // Used to animate the visibility change of settings button.
   scoped_ptr<ui::SlideAnimation> settings_button_animator_;
   gfx::Rect settings_button_full_bounds_;
   gfx::Rect settings_button_zero_bounds_;
   bool is_settings_button_visible_;
 
   DISALLOW_COPY_AND_ASSIGN(PanelBrowserFrameView);
 };
 
 #endif  // CHROME_BROWSER_UI_PANELS_PANEL_BROWSER_FRAME_VIEW_H_