Change the scale factor of texture_size from the layer's one to an estimation.

ui/compositor/compositor.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_COMPOSITOR_COMPOSITOR_H_
 #define UI_COMPOSITOR_COMPOSITOR_H_
 
 #include "base/hash_tables.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 76 matching lines @@
 
   scoped_refptr<gfx::GLShareGroup> share_group_;
 
   DISALLOW_COPY_AND_ASSIGN(DefaultContextFactory);
 };
 
 // Texture provide an abstraction over the external texture that can be passed
 // to a layer.
 class COMPOSITOR_EXPORT Texture : public base::RefCounted<Texture> {
  public:
-  Texture(bool flipped, const gfx::Size& size);
+  Texture(bool flipped, const gfx::Size& size, float device_scale_factor);
 
   unsigned int texture_id() const { return texture_id_; }
   void set_texture_id(unsigned int id) { texture_id_ = id; }
   bool flipped() const { return flipped_; }
   gfx::Size size() const { return size_; }
+  float device_scale_factor() const { return device_scale_factor_; }
   virtual WebKit::WebGraphicsContext3D* HostContext3D() = 0;
 
  protected:
   virtual ~Texture();
 
  private:
   friend class base::RefCounted<Texture>;
 
   unsigned int texture_id_;
   bool flipped_;
   gfx::Size size_;  // in pixel
+  float device_scale_factor_;
 
   DISALLOW_COPY_AND_ASSIGN(Texture);
 };
 
 // An interface to allow the compositor to communicate with its owner.
 class COMPOSITOR_EXPORT CompositorDelegate {
  public:
   // Requests the owner to schedule a redraw of the layer tree.
   virtual void ScheduleDraw() = 0;
 
@@ skipping 127 matching lines @@
   int last_ended_frame_;
 
   bool disable_schedule_composite_;
 
   DISALLOW_COPY_AND_ASSIGN(Compositor);
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_COMPOSITOR_H_