Add support for multiple roots to the client lib.

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 <map>
 
 #include "base/basictypes.h"
@@ skipping 16 matching lines @@
 //
 // TODO: displays
 class ViewManager {
  public:
   ~ViewManager();
 
   // |ready_callback| is run when the ViewManager connection is established
   // and ready to use.
   static void Create(
       Application* application,
-      const base::Callback<void(ViewManager*)> ready_callback);
+      const base::Callback<void(ViewManager*)>& root_added_callback);
   // Blocks until ViewManager is ready to use.
-  static ViewManager* CreateBlocking(Application* application);
+  static ViewManager* CreateBlocking(
+      Application* application,
+      const base::Callback<void(ViewManager*)>& root_added_callback);
 
-  ViewTreeNode* tree() { return tree_; }
+  const std::vector<ViewTreeNode*>& roots() { return roots_; }
 
   ViewTreeNode* GetNodeById(TransportNodeId id);
   View* GetViewById(TransportViewId id);
 
-  void Embed(const String& url, ViewTreeNode* node);
-
  private:
   friend class ViewManagerPrivate;
   typedef std::map<TransportNodeId, ViewTreeNode*> IdToNodeMap;
   typedef std::map<TransportViewId, View*> IdToViewMap;
 
   ViewManager(Application* application,
-              const base::Callback<void(ViewManager*)> ready_callback);
+              const base::Callback<void(ViewManager*)>& root_added_callback);
 
-  base::Callback<void(ViewManager*)> ready_callback_;
+  base::Callback<void(ViewManager*)> root_added_callback_;
 
   ViewManagerSynchronizer* synchronizer_;
-  ViewTreeNode* tree_;
+
+  std::vector<ViewTreeNode*> roots_;
 
   IdToNodeMap nodes_;
   IdToViewMap views_;
 
   DISALLOW_COPY_AND_ASSIGN(ViewManager);
 };
 
 }  // namespace view_manager
 }  // namespace mojo
 
 #endif  // MOJO_SERVICES_PUBLIC_CPP_VIEW_MANAGER_VIEW_MANAGER_H_