Make ServiceRegistry (which implements) ApplicationConnection just wrap a ServiceProviderImpl.

mojo/public/cpp/application/application_connection.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_CONNECTION_H_
 #define MOJO_PUBLIC_APPLICATION_APPLICATION_CONNECTION_H_
 
 #include <string>
 
 #include "mojo/public/cpp/application/lib/interface_factory_connector.h"
+#include "mojo/public/cpp/application/service_provider_impl.h"
 #include "mojo/public/interfaces/application/service_provider.mojom.h"
 
 namespace mojo {
 
 struct ConnectionContext;
 class ServiceConnector;
 
 // Represents a connection to another application. An instance of this class is
 // passed to ApplicationDelegate's ConfigureIncomingConnection() method each
 // time a connection is made to this app, and is returned by the
@@ skipping 22 matching lines @@
 
   // Makes Interface available as a service to the remote application.
   // |factory| will create implementations of Interface on demand.
   template <typename Interface>
   void AddService(InterfaceFactory<Interface>* factory) {
     SetServiceConnectorForName(
         new internal::InterfaceFactoryConnector<Interface>(factory),
         Interface::Name_);
   }
 
+  virtual ServiceProviderImpl& GetServiceProviderImpl() = 0;
+
   virtual const ConnectionContext& GetConnectionContext() const = 0;
 
   // Returns the URL that was used by the source application to establish a
   // connection to the destination application.
   //
   // When ApplicationConnection is representing an incoming connection this can
   // be different than the URL the application was initially loaded from, if the
   // application handles multiple URLs. Note that this is the URL after all
   // URL rewriting and HTTP redirects have been performed.
   //
   // When ApplicationConnection is representing and outgoing connection, this
   // will be the same as the value returned by GetRemoveApplicationURL().
   virtual const std::string& GetConnectionURL() = 0;
 
   // Returns the URL identifying the remote application on this connection.
   virtual const std::string& GetRemoteApplicationURL() = 0;
 
  private:
   virtual void SetServiceConnectorForName(ServiceConnector* service_connector,
                                           const std::string& name) = 0;
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_APPLICATION_APPLICATION_CONNECTION_H_