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

ui/views/controls/label.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_CONTROLS_LABEL_H_
 #define UI_VIEWS_CONTROLS_LABEL_H_
 #pragma once
 
 #include <string>
 
@@ skipping 173 matching lines @@
   // Gets the tooltip text for labels that are wider than their bounds, except
   // when the label is multiline, in which case it just returns false (no
   // tooltip).  If a custom tooltip has been specified with SetTooltipText()
   // it is returned instead.
   virtual bool GetTooltipText(const gfx::Point& p,
                               string16* tooltip) const OVERRIDE;
 
  protected:
   // Called by Paint to paint the text.  Override this to change how
   // text is painted.
-  virtual void PaintText(gfx::Canvas* canvas,
+  virtual void PaintText(gfx::CanvasSkia* canvas,
                          const string16& text,
                          const gfx::Rect& text_bounds,
                          int flags);
 
   void invalidate_text_size() { text_size_valid_ = false; }
 
   virtual gfx::Size GetTextSize() const;
 
   SkColor disabled_color() const { return actual_disabled_color_; }
 
   // Overridden from View:
   // Overridden to dirty our text bounds if we're multi-line.
   virtual void OnBoundsChanged(const gfx::Rect& previous_bounds) OVERRIDE;
-  virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
+  virtual void OnPaint(gfx::CanvasSkia* canvas) OVERRIDE;
   // If the mouse is over the label, and a mouse over background has been
   // specified, its used. Otherwise super's implementation is invoked.
-  virtual void OnPaintBackground(gfx::Canvas* canvas) OVERRIDE;
+  virtual void OnPaintBackground(gfx::CanvasSkia* canvas) OVERRIDE;
 
  private:
   // These tests call CalculateDrawStringParams in order to verify the
   // calculations done for drawing text.
   FRIEND_TEST_ALL_PREFIXES(LabelTest, DrawSingleLineString);
   FRIEND_TEST_ALL_PREFIXES(LabelTest, DrawMultiLineString);
   FRIEND_TEST_ALL_PREFIXES(LabelTest, DrawSingleLineStringInRTL);
   FRIEND_TEST_ALL_PREFIXES(LabelTest, DrawMultiLineStringInRTL);
   FRIEND_TEST_ALL_PREFIXES(LabelTest, AutoDetectDirectionality);
 
@@ skipping 57 matching lines @@
   // allows this view to reserve space for a focus border that it otherwise
   // might not have because it is not itself focusable.
   bool has_focus_border_;
 
   DISALLOW_COPY_AND_ASSIGN(Label);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_LABEL_H_