Allow EmbedRoot to be called multiple times.

mojo/services/public/cpp/view_manager/view_manager.h

 // 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.
 
 #ifndef MOJO_SERVICES_PUBLIC_CPP_VIEW_MANAGER_VIEW_MANAGER_H_
 #define MOJO_SERVICES_PUBLIC_CPP_VIEW_MANAGER_VIEW_MANAGER_H_
 
 #include <string>
 #include <vector>
 
 #include "mojo/services/public/cpp/view_manager/types.h"
 #include "mojo/services/public/interfaces/input_events/input_events.mojom.h"
 
 namespace mojo {
 class ApplicationConnection;
 namespace view_manager {
 
 class Node;
 class View;
-class ViewEventDispatcher;
 class ViewManagerDelegate;
+class WindowManagerDelegate;
 
 class ViewManager {
  public:
   // Delegate is owned by the caller.
   static void ConfigureIncomingConnection(ApplicationConnection* connection,
                                           ViewManagerDelegate* delegate);
 
-  // Sets the event dispatcher. Can only be called by the app rendering to the
-  // root Node of the hierarchy.
-  virtual void SetEventDispatcher(ViewEventDispatcher* dispatcher) = 0;
+  // Sets the window manager delegate. Can only be called by the app embedded at
+  // the service root node.
+  virtual void SetWindowManagerDelegate(
+      WindowManagerDelegate* window_manager_delegate) = 0;
 
   // Dispatches the supplied event to the specified View. Can be called only
-  // by the application that called SetEventDispatcher().
+  // by the application that called SetWindowManagerDelegate().
   virtual void DispatchEvent(View* target, EventPtr event) = 0;
 
   // Returns the URL of the application that embedded this application.
   virtual const std::string& GetEmbedderURL() const = 0;
 
   // Returns all root nodes known to this connection.
   virtual const std::vector<Node*>& GetRoots() const = 0;
 
   // Returns a Node or View known to this connection.
   virtual Node* GetNodeById(Id id) = 0;
   virtual View* GetViewById(Id id) = 0;
 
  protected:
   virtual ~ViewManager() {}
 
 };
 
 }  // namespace view_manager
 }  // namespace mojo
 
 #endif  // MOJO_SERVICES_PUBLIC_CPP_VIEW_MANAGER_VIEW_MANAGER_H_