Make delegated software renderer work on Mac

cc/output/software_output_device.h

 // Copyright 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 CC_OUTPUT_SOFTWARE_OUTPUT_DEVICE_H_
 #define CC_OUTPUT_SOFTWARE_OUTPUT_DEVICE_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "cc/base/cc_export.h"
@@ skipping 18 matching lines @@
 // This is a "tear-off" class providing software drawing support to
 // OutputSurface, such as to a platform-provided window framebuffer.
 class CC_EXPORT SoftwareOutputDevice {
  public:
   SoftwareOutputDevice();
   virtual ~SoftwareOutputDevice();
 
   // Discards any pre-existing backing buffers and allocates memory for a
   // software device of |size|. This must be called before the
   // |SoftwareOutputDevice| can be used in other ways.
-  virtual void Resize(const gfx::Size& size);
+  virtual void Resize(const gfx::Size& pixel_size, float scale_factor);
 
   // Called on BeginDrawingFrame. The compositor will draw into the returned
   // SkCanvas. The |SoftwareOutputDevice| implementation needs to provide a
   // valid SkCanvas of at least size |damage_rect|. This class retains ownership
   // of the SkCanvas.
   virtual SkCanvas* BeginPaint(const gfx::Rect& damage_rect);
 
   // Called on FinishDrawingFrame. The compositor will no longer mutate the the
   // SkCanvas instance returned by |BeginPaint| and should discard any reference
   // that it holds to it.
@@ skipping 17 matching lines @@
   // Called in response to receiving a SwapBuffersAck. At this point, software
   // frame identified by id can be reused or discarded as it is no longer being
   // displayed.
   virtual void ReclaimSoftwareFrame(unsigned id);
 
   // VSyncProvider used to update the timer used to schedule draws with the
   // hardware vsync. Return NULL if a provider doesn't exist.
   virtual gfx::VSyncProvider* GetVSyncProvider();
 
  protected:
-  gfx::Size viewport_size_;
+  gfx::Size viewport_pixel_size_;
+  float scale_factor_;
   gfx::Rect damage_rect_;
   skia::RefPtr<SkCanvas> canvas_;
   scoped_ptr<gfx::VSyncProvider> vsync_provider_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SoftwareOutputDevice);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_SOFTWARE_OUTPUT_DEVICE_H_