ash: Clean up system background layer.

ui/aura/root_window.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 UI_AURA_ROOT_WINDOW_H_
 #define UI_AURA_ROOT_WINDOW_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop.h"
 #include "ui/aura/aura_export.h"
 #include "ui/aura/client/capture_delegate.h"
 #include "ui/aura/root_window_host_delegate.h"
 #include "ui/aura/window.h"
 #include "ui/base/cursor/cursor.h"
 #include "ui/base/events/event_constants.h"
 #include "ui/base/events/event_dispatcher.h"
 #include "ui/base/gestures/gesture_recognizer.h"
 #include "ui/base/gestures/gesture_types.h"
 #include "ui/compositor/compositor.h"
 #include "ui/compositor/compositor_observer.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/point.h"
 
+class SkCanvas;
+
 namespace gfx {
 class Size;
 class Transform;
 }
 
 namespace ui {
 class GestureEvent;
 class GestureRecognizer;
 class KeyEvent;
 class LayerAnimationSequence;
@@ skipping 194 matching lines @@
   // release before we resume normal operation.
   void HoldMouseMoves();
   void ReleaseMouseMoves();
 
   // Creates a compositor lock.
   scoped_refptr<CompositorLock> GetCompositorLock();
 
   // Sets if the window should be focused when shown.
   void SetFocusWhenShown(bool focus_when_shown);
 
-  // Grabs the snapshot of the root window by using the platform-dependent APIs.
+  // Copies |source_bounds| from the root window (as displayed on the host
+  // machine) to |canvas| at offset |dest_offset|.
+  bool CopyAreaToSkCanvas(const gfx::Rect& source_bounds,
+                          const gfx::Point& dest_offset,
+                          SkCanvas* canvas);
+
+  // Grabs a snapshot of the root window using platform-specific APIs, encodes
+  // it in PNG format, and saves it to |png_representation|.
   bool GrabSnapshot(const gfx::Rect& snapshot_bounds,
                     std::vector<unsigned char>* png_representation);
 
   // Gets the last location seen in a mouse event in this root window's
   // coordinates. This may return a point outside the root window's bounds.
   gfx::Point GetLastMouseLocationInRoot() const;
 
   // Overridden from Window:
   virtual RootWindow* GetRootWindow() OVERRIDE;
   virtual const RootWindow* GetRootWindow() const OVERRIDE;
@@ skipping 157 matching lines @@
 
   CompositorLock* compositor_lock_;
   bool draw_on_compositor_unlock_;
 
   DISALLOW_COPY_AND_ASSIGN(RootWindow);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_ROOT_WINDOW_H_