ui/gfx: Make gfx::Canvas inherit from gfx::CanvasSkia.

ui/views/controls/menu/menu_item_view.h

Index: ui/views/controls/menu/menu_item_view.h
diff --git a/ui/views/controls/menu/menu_item_view.h b/ui/views/controls/menu/menu_item_view.h
index dbc22f67ad15655a6bfa1a43e1ecbeb82c1278bd..f2470e908655e0d9494e9feb4f95d73cc98b44aa 100644
--- a/ui/views/controls/menu/menu_item_view.h
+++ b/ui/views/controls/menu/menu_item_view.h
@@ -249,7 +249,7 @@ class VIEWS_EXPORT MenuItemView : public View {
   int GetCommand() const { return command_; }
 
   // Paints the menu item.
-  virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
+  virtual void OnPaint(gfx::CanvasSkia* canvas) OVERRIDE;
 
   // Returns the preferred size of this item.
   virtual gfx::Size GetPreferredSize() OVERRIDE;
@@ -355,20 +355,20 @@ class VIEWS_EXPORT MenuItemView : public View {
   // Actual paint implementation. If mode is PB_FOR_DRAG, portions of the menu
   // are not rendered.
   enum PaintButtonMode { PB_NORMAL, PB_FOR_DRAG };
-  void PaintButton(gfx::Canvas* canvas, PaintButtonMode mode);
+  void PaintButton(gfx::CanvasSkia* canvas, PaintButtonMode mode);
 
 #if defined(OS_WIN)
   enum SelectionState { SELECTED, UNSELECTED };
 
   // Paints the check/radio button indicator.
-  void PaintCheck(gfx::Canvas* canvas,
+  void PaintCheck(gfx::CanvasSkia* canvas,
                   gfx::NativeTheme::State state,
                   SelectionState selection_state,
                   const MenuConfig& config);
 #endif
 
   // Paints the accelerator.
-  void PaintAccelerator(gfx::Canvas* canvas);
+  void PaintAccelerator(gfx::CanvasSkia* canvas);
 
   // Destroys the window used to display this menu and recursively destroys
   // the windows used to display all descendants.