Update Panel mininimize/restore button on strip and expansion state change.

chrome/browser/ui/panels/panel_browser_frame_view.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_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 17 matching lines @@
 }
 
 class PanelBrowserFrameView : public BrowserNonClientFrameView,
                               public views::ButtonListener,
                               public TabIconView::TabIconViewModel {
  public:
   PanelBrowserFrameView(BrowserFrame* frame, PanelBrowserView* browser_view);
   virtual ~PanelBrowserFrameView();
 
   void UpdateTitleBar();
+  void UpdateTitleBarMinimizeRestoreButtonVisibility();
 
   // Returns the height of the entire nonclient top border, including the window
   // frame, any title area, and any connected client edge.
   int NonClientTopBorderHeight() const;
 
   // Returns the size of the non-client area, that is, the window size minus
   // the size of the client area.
   gfx::Size NonClientAreaSize() const;
 
   // Returns true if the frame window is showing only the titlebar.
@@ skipping 81 matching lines @@
   views::ImageButton* minimize_button_;
   views::ImageButton* restore_button_;
   TabIconView* title_icon_;
   views::Label* title_label_;
   gfx::Rect client_view_bounds_;
 
   DISALLOW_COPY_AND_ASSIGN(PanelBrowserFrameView);
 };
 
 #endif  // CHROME_BROWSER_UI_PANELS_PANEL_BROWSER_FRAME_VIEW_H_