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

content/browser/renderer_host/image_transport_factory.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 CONTENT_BROWSER_RENDERER_HOST_IMAGE_TRANSPORT_FACTORY_H_
 #define CONTENT_BROWSER_RENDERER_HOST_IMAGE_TRANSPORT_FACTORY_H_
 
 #include "base/memory/ref_counted.h"
 #include "ui/gfx/native_widget_types.h"
 
@@ skipping 71 matching lines @@
       unsigned int texture_id) = 0;
 
   // Gets a GLHelper instance, associated with the shared context. This
   // GLHelper will get destroyed whenever the shared context is lost
   // (ImageTransportFactoryObserver::OnLostResources is called).
   virtual content::GLHelper* GetGLHelper() = 0;
 
   // Inserts a SyncPoint into the shared context.
   virtual uint32 InsertSyncPoint() = 0;
 
+  // Sets the device scale factor.
+  virtual void SetDeviceScaleFactor(float device_scale_factor) = 0;

[piman, 2012/09/21 00:59:34]

Because ImageTransportFactory is a singleton, that doesn't really work. It's
probably better to pass it to CreateTransportClient/CreateOwnedTexture.

[Jun Mukai, 2012/09/21 02:28:52]

removed this and added an argument to CreateTransportClient/OwnedTexture.

+
   virtual void AddObserver(ImageTransportFactoryObserver* observer) = 0;
   virtual void RemoveObserver(ImageTransportFactoryObserver* observer) = 0;
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_IMAGE_TRANSPORT_FACTORY_H_