Pass a ui::PaintContext from ui::Layer to layer delegates.

ui/views/widget/native_widget_delegate.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_VIEWS_WIDGET_NATIVE_WIDGET_DELEGATE_H_
 #define UI_VIEWS_WIDGET_NATIVE_WIDGET_DELEGATE_H_
 
 #include <vector>
 
 #include "ui/events/event_constants.h"
 #include "ui/views/views_export.h"
 
 namespace gfx {
 class Canvas;
 class Path;
 class Point;
 class Size;
 }
 
 namespace ui {
 class GestureEvent;
 class KeyEvent;
 class Layer;
 class MouseEvent;
+class PaintContext;
+class ScrollEvent;
 class TouchEvent;
-class ScrollEvent;
 }
 
 namespace views {
 class InputMethod;
 class Widget;
 
 namespace internal {
 
 ////////////////////////////////////////////////////////////////////////////////
 // NativeWidgetDelegate
@@ skipping 66 matching lines @@
   virtual void OnNativeWidgetEndUserBoundsChange() = 0;
 
   // Returns true if the delegate has a FocusManager.
   virtual bool HasFocusManager() const = 0;
 
   // Paints the widget using acceleration. If the widget is not using
   // accelerated painting this returns false and does nothing.
   virtual bool OnNativeWidgetPaintAccelerated(
       const gfx::Rect& dirty_region) = 0;
 
-  // Paints the rootview in the canvas. This will also refresh the compositor
-  // tree if necessary when accelerated painting is enabled.
-  virtual void OnNativeWidgetPaint(gfx::Canvas* canvas) = 0;
+  // Paints the rootview in the context. This will also refresh the compositor
+  // tree if necessary.
+  virtual void OnNativeWidgetPaint(const ui::PaintContext& context) = 0;
 
   // Returns the non-client component (see ui/base/hit_test.h) containing
   // |point|, in client coordinates.
   virtual int GetNonClientComponent(const gfx::Point& point) = 0;
 
   // Mouse and key event handlers.
   virtual void OnKeyEvent(ui::KeyEvent* event) = 0;
   virtual void OnMouseEvent(ui::MouseEvent* event) = 0;
   virtual void OnMouseCaptureLost() = 0;
 
@@ skipping 27 matching lines @@
   // later.  Returns true if the initial focus has been set or the window should
   // not set the initial focus, or false if the caller should set the initial
   // focus (if any).
   virtual bool SetInitialFocus(ui::WindowShowState show_state) = 0;
 };
 
 }  // namespace internal
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_NATIVE_WIDGET_DELEGATE_H_