Consolidates view_manager typedefs

mojo/services/public/cpp/view_manager/view.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_H_
 #define MOJO_SERVICES_PUBLIC_CPP_VIEW_MANAGER_VIEW_H_
 
 #include "base/basictypes.h"
 #include "base/observer_list.h"
 #include "mojo/services/public/cpp/view_manager/view_manager_types.h"
 #include "third_party/skia/include/core/SkColor.h"
 
 class SkBitmap;
 
 namespace mojo {
 namespace view_manager {
 
 class ViewManager;
 class ViewObserver;
 class ViewTreeNode;
 
 // Views are owned by the ViewManager.
 class View {
  public:
   static View* Create(ViewManager* manager);
 
   void Destroy();
 
-  TransportViewId id() const { return id_; }
+  Id id() const { return id_; }
   ViewTreeNode* node() { return node_; }
 
   void AddObserver(ViewObserver* observer);
   void RemoveObserver(ViewObserver* observer);
 
   // TODO(beng): temporary only.
   void SetContents(const SkBitmap& contents);
   void SetColor(SkColor color);
 
  private:
   friend class ViewPrivate;
 
   explicit View(ViewManager* manager);
   View();
   ~View();
 
   void LocalDestroy();
 
-  TransportViewId id_;
+  Id id_;
   ViewTreeNode* node_;
   ViewManager* manager_;
 
   ObserverList<ViewObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(View);
 };
 
 }  // namespace view_manager
 }  // namespace mojo
 
 #endif  // MOJO_SERVICES_PUBLIC_CPP_VIEW_MANAGER_VIEW_H_