[Ozone] Fix build

ui/ozone/platform/dri/dri_surface.h

 // Copyright 2014 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_OZONE_PLATFORM_DRI_DRI_SURFACE_H_
 #define UI_OZONE_PLATFORM_DRI_DRI_SURFACE_H_
 
 #include "base/memory/ref_counted.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/ozone/public/surface_ozone_canvas.h"
 
-class SkCanvas;
 class SkSurface;
 
 namespace ui {
 
 class DriBuffer;
 class DriWindowDelegate;
 class DriWrapper;
 class HardwareDisplayController;
 
 class DriSurface : public SurfaceOzoneCanvas {
  public:
   DriSurface(DriWindowDelegate* window_delegate, DriWrapper* dri);
   ~DriSurface() override;
 
   // SurfaceOzoneCanvas:
-  skia::RefPtr<SkCanvas> GetCanvas() override;
+  skia::RefPtr<SkSurface> GetSurface() override;
   void ResizeCanvas(const gfx::Size& viewport_size) override;
   void PresentCanvas(const gfx::Rect& damage) override;
   scoped_ptr<gfx::VSyncProvider> CreateVSyncProvider() override;
 
  private:
   void UpdateNativeSurface(const gfx::Rect& damage);
 
   DriWindowDelegate* window_delegate_;
 
   // Stores the connection to the graphics card. Pointer not owned by this
   // class.
   DriWrapper* dri_;
 
   // The actual buffers used for painting.
   scoped_refptr<DriBuffer> buffers_[2];
 
   // Keeps track of which bitmap is |buffers_| is the frontbuffer.
   int front_buffer_;
 
   skia::RefPtr<SkSurface> surface_;
   gfx::Rect last_damage_;
 
   DISALLOW_COPY_AND_ASSIGN(DriSurface);
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PLATFORM_DRI_DRI_SURFACE_H_