Cleanup to keep panel from manipulating its panel strip assignment directly.

chrome/browser/ui/panels/docked_panel_strip.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_DOCKED_PANEL_STRIP_H_
 #define CHROME_BROWSER_UI_PANELS_DOCKED_PANEL_STRIP_H_
 #pragma once
 
 #include <list>
 #include <set>
@@ skipping 25 matching lines @@
 
   // Rearranges the positions of the panels in the strip.
   // Handles moving panels to/from overflow area as needed.
   // This is called when the display space has been changed, i.e. working
   // area being changed or a panel being closed.
   virtual void RefreshLayout() OVERRIDE;
 
   // Adds a panel to the strip. The panel may be a newly created panel or one
   // that is transitioning from another grouping of panels.
   virtual void AddPanel(Panel* panel) OVERRIDE;
-  virtual bool RemovePanel(Panel* panel) OVERRIDE;
+  virtual void RemovePanel(Panel* panel) OVERRIDE;
   virtual void CloseAll() OVERRIDE;
   virtual void ResizePanelWindow(
       Panel* panel,
       const gfx::Size& preferred_window_size) OVERRIDE;
   virtual void OnPanelAttentionStateChanged(Panel* panel) OVERRIDE;
   virtual void ActivatePanel(Panel* panel) OVERRIDE;
   virtual void MinimizePanel(Panel* panel) OVERRIDE;
   virtual void RestorePanel(Panel* panel) OVERRIDE;
   virtual bool CanShowPanelAsActive(const Panel* panel) const OVERRIDE;
   virtual bool CanDragPanel(const Panel* panel) const OVERRIDE;
@@ skipping 113 matching lines @@
   // Absolute minimum width and height for panels, including non-client area.
   // Should only be big enough to accomodate a close button on the reasonably
   // recognisable titlebar.
   static const int kPanelMinWidth;
   static const int kPanelMinHeight;
 
   DISALLOW_COPY_AND_ASSIGN(DockedPanelStrip);
 };
 
 #endif  // CHROME_BROWSER_UI_PANELS_DOCKED_PANEL_STRIP_H_