Adds more to viewmanager

mojo/services/view_manager/root_node_manager.h

Index: mojo/services/view_manager/root_node_manager.h
diff --git a/mojo/services/view_manager/root_node_manager.h b/mojo/services/view_manager/root_node_manager.h
index aecfa8b7381aa2fea8b55988868543838688dc88..98f347e0c9ed3746263aed3594f92c9c7e94da1d 100644
--- a/mojo/services/view_manager/root_node_manager.h
+++ b/mojo/services/view_manager/root_node_manager.h
@@ -50,13 +50,23 @@ class MOJO_VIEW_MANAGER_EXPORT RootNodeManager
   void AddConnection(ViewManagerConnection* connection);
   void RemoveConnection(ViewManagerConnection* connection);
 
+  // Returns the connection by id.
+  ViewManagerConnection* GetConnection(uint16_t connection_id);
+
   // Returns the Node identified by |id|.
   Node* GetNode(const NodeId& id);
 
-  // Notifies all ViewManagerConnections of a hierarchy change.
+  // Returns the View identified by |id|.
+  View* GetView(const ViewId& id);
+
+  // These functions trivially delegate to all ViewManagerConnections, which in
+  // term notify their clients.
   void NotifyNodeHierarchyChanged(const NodeId& node,
                                   const NodeId& new_parent,
                                   const NodeId& old_parent);
+  void NotifyNodeViewReplaced(const NodeId& node,
+                              const ViewId& new_view_id,
+                              const ViewId& old_view_id);
 
  private:
   // Tracks a change.
@@ -94,6 +104,9 @@ class MOJO_VIEW_MANAGER_EXPORT RootNodeManager
   virtual void OnNodeHierarchyChanged(const NodeId& node,
                                       const NodeId& new_parent,
                                       const NodeId& old_parent) OVERRIDE;
+  virtual void OnNodeViewReplaced(const NodeId& node,
+                                  const ViewId& new_view_id,
+                                  const ViewId& old_view_id) OVERRIDE;
 
   // ID to use for next ViewManagerConnection.
   uint16_t next_connection_id_;