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

ui/compositor/compositor.cc

 // 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.
 
 #include "ui/compositor/compositor.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/threading/thread_restrictions.h"
@@ skipping 106 matching lines @@
   if (!offscreen) {
     context->makeContextCurrent();
     gfx::GLContext* gl_context = gfx::GLContext::GetCurrent();
     bool vsync = !command_line->HasSwitch(switches::kDisableUIVsync);
     gl_context->SetSwapInterval(vsync ? 1 : 0);
     gl_context->ReleaseCurrent(NULL);
   }
   return context;
 }
 
-Texture::Texture(bool flipped, const gfx::Size& size)
+Texture::Texture(bool flipped, const gfx::Size& size, float device_scale_factor)
     : texture_id_(0),
       flipped_(flipped),
-      size_(size) {
+      size_(size),
+      device_scale_factor_(device_scale_factor) {
 }
 
 Texture::~Texture() {
 }
 
 Compositor::Compositor(CompositorDelegate* delegate,
                        gfx::AcceleratedWidget widget)
     : delegate_(delegate),
       root_layer_(NULL),
       widget_(widget),
@@ skipping 290 matching lines @@
 
 COMPOSITOR_EXPORT void DisableTestCompositor() {
   test_compositor_enabled = false;
 }
 
 COMPOSITOR_EXPORT bool IsTestCompositorEnabled() {
   return test_compositor_enabled;
 }
 
 }  // namespace ui