aura: Try to make Linux host resize code more reliable.

ui/aura/desktop_host.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 UI_AURA_DESKTOP_HOST_H_
 #define UI_AURA_DESKTOP_HOST_H_
 #pragma once
 
 #include "base/message_loop.h"
 #include "ui/aura/cursor.h"
@@ skipping 11 matching lines @@
 
 // DesktopHost bridges between a native window and the embedded Desktop. It
 // provides the accelerated widget and maps events from the native os to aura.
 class DesktopHost : public MessageLoop::Dispatcher {
  public:
   virtual ~DesktopHost() {}
 
   // Creates a new DesktopHost. The caller owns the returned value.
   static DesktopHost* Create(const gfx::Rect& bounds);
 
+  // Returns the actual size of the display.
+  // (gfx::Screen only reports on the virtual desktop exposed by Aura.)
+  static gfx::Size GetNativeDisplaySize();
+
   // Sets the Desktop this DesktopHost is hosting. DesktopHost does not own the
   // Desktop.
   virtual void SetDesktop(Desktop* desktop) = 0;
 
   // Returns the accelerated widget.
   virtual gfx::AcceleratedWidget GetAcceleratedWidget() = 0;
 
   // Shows the DesktopHost.
   virtual void Show() = 0;
 
   // Gets/Sets the size of the DesktopHost.
   virtual gfx::Size GetSize() const = 0;
   virtual void SetSize(const gfx::Size& size) = 0;
 
   // Sets the currently displayed cursor.
   virtual void SetCursor(gfx::NativeCursor cursor) = 0;
 
   // Queries the mouse's current position relative to the host window.
   // The position is constrained within the host window.
   // You should probably call Desktop::last_mouse_location() instead; this
   // method can be expensive.
   virtual gfx::Point QueryMouseLocation() = 0;
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_DESKTOP_HOST_H_