Initial cut at layerless windows.

ui/compositor/layer.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_COMPOSITOR_LAYER_H_
 #define UI_COMPOSITOR_LAYER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 269 matching lines @@
 
   // Schedules a redraw of the layer tree at the compositor.
   // Note that this _does not_ invalidate any region of this layer; use
   // SchedulePaint() for that.
   void ScheduleDraw();
 
   // Sends damaged rectangles recorded in |damaged_region_| to
   // |compostior_| to repaint the content.
   void SendDamagedRects();
 
+  const SkRegion& damaged_region() const { return damaged_region_; }
+
   // Suppresses painting the content by disgarding damaged region and ignoring
   // new paint requests.
   void SuppressPaint();
 
   // Notifies the layer that the device scale factor has changed.
   void OnDeviceScaleFactorChanged(float device_scale_factor);
 
   // Sets whether the layer should scale its content. If true, the canvas will
   // be scaled in software rendering mode before it is passed to
   // |LayerDelegate::OnPaint|.
@@ skipping 192 matching lines @@
   // The size of the delegated frame in DIP, set when SetShowDelegatedContent
   // was called.
   gfx::Size delegated_frame_size_in_dip_;
 
   DISALLOW_COPY_AND_ASSIGN(Layer);
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_LAYER_H_