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

chrome/browser/ui/views/detachable_toolbar_view.h

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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 CHROME_BROWSER_UI_VIEWS_DETACHABLE_TOOLBAR_VIEW_H_
 #define CHROME_BROWSER_UI_VIEWS_DETACHABLE_TOOLBAR_VIEW_H_
 #pragma once
 
 #include "ui/views/accessible_pane_view.h"
 
 struct SkRect;
@@ skipping 15 matching lines @@
 
   // Gets the current state of the resize animation (show/hide).
   virtual double GetAnimationValue() const = 0;
 
   // Gets the current amount of overlap atop the browser toolbar.
   virtual int GetToolbarOverlap() const = 0;
 
   // Paints the background (including the theme image behind content area) when
   // the bar/shelf is attached to the top toolbar.  |background_origin| is the
   // origin to use for painting the theme image.
-  static void PaintBackgroundAttachedMode(gfx::Canvas* canvas,
+  static void PaintBackgroundAttachedMode(gfx::CanvasSkia* canvas,
                                           views::View* view,
                                           const gfx::Point& background_origin);
 
   // Calculate the rect for the content area of the bar/shelf. This is only
   // needed when the bar/shelf is detached from the Chrome frame (otherwise the
   // content area is the whole area of the bar/shelf. When detached, however,
   // only a small round rectangle is for drawing our content on. This calculates
   // how big this area is, where it is located within the shelf and how round
   // the edges should be.
   static void CalculateContentArea(double animation_state,
                                    double horizontal_padding,
                                    double vertical_padding,
                                    SkRect* rect,
                                    double* roundness,
                                    views::View* view);
 
   // Paint the horizontal border separating the shelf/bar from the page content.
-  static void PaintHorizontalBorder(gfx::Canvas* canvas,
+  static void PaintHorizontalBorder(gfx::CanvasSkia* canvas,
                                     DetachableToolbarView* view);
 
   // Paint the background of the content area (the surface behind the
   // bookmarks). |rect| is the rectangle to paint the background within.
   // |roundness| describes the roundness of the corners.
-  static void PaintContentAreaBackground(gfx::Canvas* canvas,
+  static void PaintContentAreaBackground(gfx::CanvasSkia* canvas,
                                          ui::ThemeProvider* theme_provider,
                                          const SkRect& rect,
                                          double roundness);
   // Paint the border around the content area (when in detached mode).
-  static void PaintContentAreaBorder(gfx::Canvas* canvas,
+  static void PaintContentAreaBorder(gfx::CanvasSkia* canvas,
                                      ui::ThemeProvider* theme_provider,
                                      const SkRect& rect,
                                      double roundness);
 
   // Paint a themed gradient divider at location |x|. |height| is the full
   // height of the view you want to paint the divider into, not the height of
   // the divider. The height of the divider will become:
   //   |height| - 2 * |vertical_padding|.
   // The color of the divider is a gradient starting with |top_color| at the
   // top, and changing into |middle_color| and then over to |bottom_color| as
   // you go further down.
-  static void PaintVerticalDivider(gfx::Canvas* canvas,
+  static void PaintVerticalDivider(gfx::CanvasSkia* canvas,
                                    int x,
                                    int height,
                                    int vertical_padding,
                                    const SkColor& top_color,
                                    const SkColor& middle_color,
                                    const SkColor& bottom_color);
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DetachableToolbarView);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_DETACHABLE_TOOLBAR_VIEW_H_