Remove ShellPtrWatcher details from public header

mojo/public/cpp/application/application_impl.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_PUBLIC_APPLICATION_APPLICATION_IMPL_H_
 #define MOJO_PUBLIC_APPLICATION_APPLICATION_IMPL_H_
 #include <vector>
 
 #include "mojo/public/cpp/application/application_connection.h"
 #include "mojo/public/cpp/application/lib/service_connector.h"
@@ skipping 52 matching lines @@
 
   // Connect to application identified by |application_url| and connect to the
   // service implementation of the interface identified by |Interface|.
   template <typename Interface>
   void ConnectToService(const std::string& application_url,
                         InterfacePtr<Interface>* ptr) {
     ConnectToApplication(application_url)->ConnectToService(ptr);
   }
 
  private:
-  class ShellPtrWatcher : public ErrorHandler {
-   public:
-    explicit ShellPtrWatcher(ApplicationImpl* impl);
-    virtual ~ShellPtrWatcher();
-    virtual void OnConnectionError() MOJO_OVERRIDE;
-   private:
-    ApplicationImpl* impl_;
-    MOJO_DISALLOW_COPY_AND_ASSIGN(ShellPtrWatcher);
-  };
+  class ShellPtrWatcher;
 
   void BindShell(ScopedMessagePipeHandle shell_handle);
   void ClearConnections();
   void OnShellError() {
     ClearConnections();
     Terminate();
   };
 
   // Quits the main run loop for this application.
   static void Terminate();
 
   // Application implementation.
   virtual void AcceptConnection(const String& requestor_url,
                                 ServiceProviderPtr provider) MOJO_OVERRIDE;
 
   typedef std::vector<internal::ServiceRegistry*> ServiceRegistryList;
   ServiceRegistryList incoming_service_registries_;
   ServiceRegistryList outgoing_service_registries_;
   ApplicationDelegate* delegate_;
   ShellPtr shell_;
-  ShellPtrWatcher shell_watch_;
+  ShellPtrWatcher* shell_watch_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(ApplicationImpl);
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_APPLICATION_APPLICATION_IMPL_H_