Sky shouldn't crash on device rotate

sky/viewer/document_view.cc

 // Copyright 2014 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 "sky/viewer/document_view.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 252 matching lines @@
 }
 
 mojo::Shell* DocumentView::Shell() {
   return shell_;
 }
 
 void DocumentView::OnViewBoundsChanged(mojo::View* view,
                                        const mojo::Rect& old_bounds,
                                        const mojo::Rect& new_bounds) {
   DCHECK_EQ(view, root_);
-  gfx::Size size = new_bounds.To<gfx::Rect>().size();
-  web_view_->resize(size);
+  float device_pixel_ratio = GetDevicePixelRatio();
+  web_view_->resize(blink::WebSize(new_bounds.width / device_pixel_ratio,
+                                   new_bounds.height / device_pixel_ratio));
 }
 
 void DocumentView::OnViewFocusChanged(mojo::View* gained_focus,
                                       mojo::View* lost_focus) {
   if (root_ == lost_focus) {
     web_view_->setFocus(false);
   } else if (root_ == gained_focus) {
     web_view_->setFocus(true);
   }
 }
@@ skipping 33 matching lines @@
 void DocumentView::StartDebuggerInspectorBackend() {
   if (!inspector_backend_) {
     inspector_host_.reset(new InspectorHostImpl(web_view_, shell_));
     inspector_backend_.reset(
         new inspector::InspectorBackendMojo(inspector_host_.get()));
   }
   inspector_backend_->Connect();
 }
 
 }  // namespace sky