ui: Introduce CanvasPainter, remove PaintContext(gfx::Canvas*).

ui/views/widget/desktop_aura/desktop_window_tree_host_win.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/views/widget/desktop_aura/desktop_window_tree_host_win.h"
 
 #include "base/win/metro.h"
 #include "third_party/skia/include/core/SkPath.h"
 #include "third_party/skia/include/core/SkRegion.h"
 #include "ui/aura/client/aura_constants.h"
@@ skipping 660 matching lines @@
 }
 
 gfx::Size DesktopWindowTreeHostWin::GetRootViewSize() const {
   return GetWidget()->GetRootView()->size();
 }
 
 void DesktopWindowTreeHostWin::ResetWindowControls() {
   GetWidget()->non_client_view()->ResetWindowControls();
 }
 
-void DesktopWindowTreeHostWin::PaintLayeredWindow(gfx::Canvas* canvas) {
-  GetWidget()->GetRootView()->Paint(ui::PaintContext(canvas));
-}
-
 gfx::NativeViewAccessible DesktopWindowTreeHostWin::GetNativeViewAccessible() {
   return GetWidget()->GetRootView()->GetNativeViewAccessible();
 }
 
 InputMethod* DesktopWindowTreeHostWin::GetInputMethod() {
   return GetWidget()->GetInputMethodDirect();
 }
 
 bool DesktopWindowTreeHostWin::ShouldHandleSystemCommands() const {
   return GetWidget()->widget_delegate()->ShouldHandleSystemCommands();
@@ skipping 267 matching lines @@
 
 // static
 DesktopWindowTreeHost* DesktopWindowTreeHost::Create(
     internal::NativeWidgetDelegate* native_widget_delegate,
     DesktopNativeWidgetAura* desktop_native_widget_aura) {
   return new DesktopWindowTreeHostWin(native_widget_delegate,
                                       desktop_native_widget_aura);
 }
 
 }  // namespace views