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

mojo/public/cpp/application/lib/service_provider_impl.cc

 // 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.
 
 #include "mojo/public/cpp/application/service_provider_impl.h"
 
 #include "mojo/public/cpp/application/service_connector.h"
 #include "mojo/public/cpp/environment/logging.h"
 
 namespace mojo {
 
 ServiceProviderImpl::ServiceProviderImpl()
     : binding_(this), fallback_service_provider_(nullptr) {
 }
 
 ServiceProviderImpl::ServiceProviderImpl(
     const ConnectionContext& connection_context,
     InterfaceRequest<ServiceProvider> service_provider_request)
-    : connection_context_(connection_context),
-      binding_(this, service_provider_request.Pass()),
-      fallback_service_provider_(nullptr) {}
+    : binding_(this), fallback_service_provider_(nullptr) {
+  if (service_provider_request.is_pending())
+    Bind(connection_context, service_provider_request.Pass());
+}
 
 ServiceProviderImpl::~ServiceProviderImpl() {}
 
 void ServiceProviderImpl::Bind(
     const ConnectionContext& connection_context,
     InterfaceRequest<ServiceProvider> service_provider_request) {
   connection_context_ = connection_context;
   binding_.Bind(service_provider_request.Pass());
 }
 
 void ServiceProviderImpl::Close() {
   if (binding_.is_bound()) {
     binding_.Close();
     connection_context_ = ConnectionContext();
   }
 }
 
 void ServiceProviderImpl::ConnectToService(
     const String& service_name,
     ScopedMessagePipeHandle client_handle) {
   bool service_found = service_connector_registry_.ConnectToService(
       connection_context_, service_name, &client_handle);
   if (!service_found && fallback_service_provider_) {
     fallback_service_provider_->ConnectToService(service_name,
                                                  client_handle.Pass());
   }
 }
 
 }  // namespace mojo