Tag TransportDIBs with the device scale factor they expect.

content/renderer/render_widget.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/renderer/render_widget.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
@@ skipping 893 matching lines @@
   DCHECK(!pending_update_params_.get());
   pending_update_params_.reset(new ViewHostMsg_UpdateRect_Params);
   pending_update_params_->dx = update.scroll_delta.x();
   pending_update_params_->dy = update.scroll_delta.y();
   pending_update_params_->scroll_rect = update.scroll_rect;
   pending_update_params_->view_size = size_;
   pending_update_params_->plugin_window_moves.swap(plugin_window_moves_);
   pending_update_params_->flags = next_paint_flags_;
   pending_update_params_->scroll_offset = GetScrollOffset();
   pending_update_params_->needs_ack = true;
+  pending_update_params_->scale_factor = device_scale_factor_;
   next_paint_flags_ = 0;
   need_update_rect_for_auto_resize_ = false;
 
   if (update.scroll_rect.IsEmpty() &&
       !is_accelerated_compositing_active_ &&
       GetBitmapForOptimizedPluginPaint(bounds, &dib, &optimized_copy_location,
                                        &optimized_copy_rect)) {
     // Only update the part of the plugin that actually changed.
     optimized_copy_rect = optimized_copy_rect.Intersect(bounds);
     pending_update_params_->bitmap = dib->id();
@@ skipping 235 matching lines @@
       !plugin_window_moves_.size()) {
     return;
   }
 
   ViewHostMsg_UpdateRect_Params params;
   params.view_size = size_;
   params.plugin_window_moves.swap(plugin_window_moves_);
   params.flags = next_paint_flags_;
   params.scroll_offset = GetScrollOffset();
   params.needs_ack = false;
+  params.scale_factor = device_scale_factor_;
 
   Send(new ViewHostMsg_UpdateRect(routing_id_, params));
   next_paint_flags_ = 0;
   need_update_rect_for_auto_resize_ = false;
 }
 
 void RenderWidget::scheduleComposite() {
   if (WebWidgetHandlesCompositorScheduling()) {
     webwidget_->composite(false);
   } else {
@@ skipping 562 matching lines @@
   }
 }
 
 bool RenderWidget::WillHandleMouseEvent(const WebKit::WebMouseEvent& event) {
   return false;
 }
 
 bool RenderWidget::WebWidgetHandlesCompositorScheduling() const {
   return false;
 }