ash: Clean up system background layer.

ui/aura/root_window.cc

 // 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.
 
 #include "ui/aura/root_window.h"
 
 #include <vector>
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
@@ skipping 428 matching lines @@
 scoped_refptr<CompositorLock> RootWindow::GetCompositorLock() {
   if (!compositor_lock_)
     compositor_lock_ = new CompositorLock(this);
   return compositor_lock_;
 }
 
 void RootWindow::SetFocusWhenShown(bool focused) {
   host_->SetFocusWhenShown(focused);
 }
 
+bool RootWindow::CopyAreaToSkCanvas(const gfx::Rect& source_bounds,
+                                    const gfx::Point& dest_offset,
+                                    SkCanvas* canvas) {
+  DCHECK(canvas);
+  DCHECK(bounds().Contains(source_bounds));
+  gfx::Rect source_pixels = ui::ConvertRectToPixel(layer(), source_bounds);
+  return host_->CopyAreaToSkCanvas(source_pixels, dest_offset, canvas);
+}
+
 bool RootWindow::GrabSnapshot(const gfx::Rect& snapshot_bounds,
                               std::vector<unsigned char>* png_representation) {
+  DCHECK(png_representation);
   DCHECK(bounds().Contains(snapshot_bounds));
   gfx::Rect snapshot_pixels = ui::ConvertRectToPixel(layer(), snapshot_bounds);
   return host_->GrabSnapshot(snapshot_pixels, png_representation);
 }
 
 gfx::Point RootWindow::GetLastMouseLocationInRoot() const {
   gfx::Point location = Env::GetInstance()->last_mouse_location();
   client::ScreenPositionClient* client = client::GetScreenPositionClient(this);
   if (client)
     client->ConvertPointFromScreen(this, &location);
@@ skipping 610 matching lines @@
 void RootWindow::UnlockCompositor() {
   DCHECK(compositor_lock_);
   compositor_lock_ = NULL;
   if (draw_on_compositor_unlock_) {
     draw_on_compositor_unlock_ = false;
     ScheduleDraw();
   }
 }
 
 }  // namespace aura