Plumb ViewportMetrics change notifications around the world and back.

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 100 matching lines @@
     mojo::ServiceProviderPtr exposed_services) {
   root_ = root;
   imported_services_ = exposed_services.Pass();
   navigator_host_.set_service_provider(imported_services_.get());
 
   if (services.is_pending())
     inspector_service_provider_impl_.Bind(services.Pass());
 
   Load(response_.Pass());
 
-  auto& bounds = root_->bounds();
-  float device_pixel_ratio = GetDevicePixelRatio();
-  web_view_->resize(blink::WebSize(bounds.width / device_pixel_ratio,
-                                   bounds.height / device_pixel_ratio));
+  UpdateRootSizeAndViewportMetrics(root_->bounds());
 
   // TODO(abarth): We should ask the view whether it is focused instead of
   // assuming that we're focused.
   web_view_->setFocus(true);
   root_->AddObserver(this);
 }
 
 void DocumentView::OnViewManagerDisconnected(mojo::ViewManager* view_manager) {
   // TODO(aa): Need to figure out how shutdown works.
 }
@@ skipping 128 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_);
+  UpdateRootSizeAndViewportMetrics(new_bounds);
+}
+
+void DocumentView::OnViewViewportMetricsChanged(
+    mojo::View* view,
+    const mojo::ViewportMetrics& old_metrics,
+    const mojo::ViewportMetrics& new_metrics) {
+  DCHECK_EQ(view, root_);
+  web_view_->setDeviceScaleFactor(GetDevicePixelRatio());
+  UpdateRootSizeAndViewportMetrics(root_->bounds());
+}
+
+void DocumentView::UpdateRootSizeAndViewportMetrics(
+    const mojo::Rect& new_bounds) {
   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) {
@@ skipping 36 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