Tag TransportDIBs with the device scale factor they expect.

content/browser/renderer_host/backing_store_win.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 "content/browser/renderer_host/backing_store_win.h"
 
 #include "base/command_line.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/public/common/content_switches.h"
@@ skipping 100 matching lines @@
 
 size_t BackingStoreWin::MemorySize() {
   return size().GetArea() * (color_depth_ / 8);
 }
 
 void BackingStoreWin::PaintToBackingStore(
     content::RenderProcessHost* process,
     TransportDIB::Id bitmap,
     const gfx::Rect& bitmap_rect,
     const std::vector<gfx::Rect>& copy_rects,
+    float scale_factor,
     const base::Closure& completion_callback,
     bool* scheduled_completion_callback) {
   *scheduled_completion_callback = false;
   if (!backing_store_dib_) {
     backing_store_dib_ = CreateDIB(hdc_, size().width(),
                                    size().height(), color_depth_);
     if (!backing_store_dib_) {
       NOTREACHED();
       return;
     }
@@ skipping 39 matching lines @@
 
 void BackingStoreWin::ScrollBackingStore(int dx, int dy,
                                          const gfx::Rect& clip_rect,
                                          const gfx::Size& view_size) {
   RECT damaged_rect, r = clip_rect.ToRECT();
   ScrollDC(hdc_, dx, dy, NULL, &r, NULL, &damaged_rect);
 
   // TODO(darin): this doesn't work if dx and dy are both non-zero!
   DCHECK(dx == 0 || dy == 0);
 }