Make <webview> use out-of-process iframe architecture.

extensions/renderer/guest_view/guest_view_container.h

Index: extensions/renderer/guest_view/guest_view_container.h
diff --git a/extensions/renderer/guest_view/guest_view_container.h b/extensions/renderer/guest_view/guest_view_container.h
index 8855dd70910fa2ec255d4ed72d2c97cab0251755..7a5a1b50fb51425daf4471772561c08615e74b55 100644
--- a/extensions/renderer/guest_view/guest_view_container.h
+++ b/extensions/renderer/guest_view/guest_view_container.h
@@ -39,6 +39,14 @@ class GuestViewContainer : public content::BrowserPluginDelegate {
   // Called to perform actions when a GuestViewContainer gets a geometry.
   virtual void OnReady() {}
 
+  // BrowserPluginGuestDelegate public implementation.
+  void SetElementInstanceID(int element_instance_id) final;
+
+ protected:
+  bool ready_;
+
+  void OnHandleCallback(const IPC::Message& message);
+
  private:
   class RenderFrameLifetimeObserver;
   friend class RenderFrameLifetimeObserver;
@@ -49,19 +57,14 @@ class GuestViewContainer : public content::BrowserPluginDelegate {
   void PerformPendingRequest();
   void HandlePendingResponseCallback(const IPC::Message& message);
 
-  void OnHandleCallback(const IPC::Message& message);
-
   // BrowserPluginDelegate implementation.
   bool OnMessageReceived(const IPC::Message& message) final;
   void Ready() final;
-  void SetElementInstanceID(int element_instance_id) final;
 
   int element_instance_id_;
   content::RenderFrame* render_frame_;
   scoped_ptr<RenderFrameLifetimeObserver> render_frame_lifetime_observer_;
 
-  bool ready_;
-
   std::deque<linked_ptr<GuestViewRequest> > pending_requests_;
   linked_ptr<GuestViewRequest> pending_response_;