Make panel adjust bounds per preferred size change notification on Windows.

chrome/browser/ui/panels/panel_browser_frame_view.h

Index: chrome/browser/ui/panels/panel_browser_frame_view.h
===================================================================
--- chrome/browser/ui/panels/panel_browser_frame_view.h	(revision 94932)
+++ chrome/browser/ui/panels/panel_browser_frame_view.h	(working copy)
@@ -43,6 +43,10 @@
   // 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;
+
  protected:
   // Overridden from BrowserNonClientFrameView:
   virtual gfx::Rect GetBoundsForTabStrip(views::View* tabstrip) const OVERRIDE;