Use Surfaces to hold delegated renderer contents.

content/browser/renderer_host/render_widget_host_view_aura.cc

Index: content/browser/renderer_host/render_widget_host_view_aura.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.cc b/content/browser/renderer_host/render_widget_host_view_aura.cc
index 205f3fcd6bae5a36b31577dbe5ea8d4bd3cc4016..e11254830aab47977ead6b33d443cf58503d8e22 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.cc
+++ b/content/browser/renderer_host/render_widget_host_view_aura.cc
@@ -430,7 +430,7 @@ class RenderWidgetHostViewAura::WindowObserver : public aura::WindowObserver {
 RenderWidgetHostViewAura::RenderWidgetHostViewAura(RenderWidgetHost* host)
     : host_(RenderWidgetHostImpl::From(host)),
       window_(new aura::Window(this)),
-      delegated_frame_host_(new DelegatedFrameHost(this)),
+      delegated_frame_host_(DelegatedFrameHost::Create(this)),
       in_shutdown_(false),
       in_bounds_changed_(false),
       is_fullscreen_(false),
@@ -458,7 +458,7 @@ RenderWidgetHostViewAura::RenderWidgetHostViewAura(RenderWidgetHost* host)
   aura::client::SetActivationDelegate(window_, this);
   aura::client::SetActivationChangeObserver(window_, this);
   aura::client::SetFocusChangeObserver(window_, this);
-  window_->set_layer_owner_delegate(delegated_frame_host_.get());
+  delegated_frame_host_->SetLayerOwner(window_);
   gfx::Screen::GetScreenFor(window_)->AddObserver(this);
 
   bool overscroll_enabled = CommandLine::ForCurrentProcess()->