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

ui/views/controls/textfield/native_textfield_views.h

Index: ui/views/controls/textfield/native_textfield_views.h
diff --git a/ui/views/controls/textfield/native_textfield_views.h b/ui/views/controls/textfield/native_textfield_views.h
index 722d2952ef6f01b95b77fe5a18c7589bc2a9bf4e..87c92ac294290755d8b73c18f4e0c22d8c51e626 100644
--- a/ui/views/controls/textfield/native_textfield_views.h
+++ b/ui/views/controls/textfield/native_textfield_views.h
@@ -24,7 +24,7 @@ class Time;
 }
 
 namespace gfx {
-class Canvas;
+class CanvasSkia;
 }
 
 namespace views {
@@ -66,7 +66,7 @@ class VIEWS_EXPORT NativeTextfieldViews : public TouchSelectionClientView,
   virtual int OnPerformDrop(const DropTargetEvent& event) OVERRIDE;
   virtual void OnDragDone() OVERRIDE;
   virtual bool OnKeyReleased(const KeyEvent& event) OVERRIDE;
-  virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
+  virtual void OnPaint(gfx::CanvasSkia* canvas) OVERRIDE;
   virtual void OnFocus() OVERRIDE;
   virtual void OnBlur() OVERRIDE;
 
@@ -182,7 +182,7 @@ class VIEWS_EXPORT NativeTextfieldViews : public TouchSelectionClientView,
   // Update the cursor_bounds and text_offset.
   void UpdateCursorBoundsAndTextOffset(size_t cursor_pos, bool insert_mode);
 
-  void PaintTextAndCursor(gfx::Canvas* canvas);
+  void PaintTextAndCursor(gfx::CanvasSkia* canvas);
 
   // Handle the keyevent.
   bool HandleKeyEvent(const KeyEvent& key_event);