First cut at "content handling" support in Mojo.

mojo/shell/network_service_loader.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/shell/network_service_loader.h"
 
 #include "base/base_paths.h"
 #include "base/files/file_path.h"
 #include "base/path_service.h"
 #include "mojo/public/cpp/application/application_connection.h"
@@ skipping 14 matching lines @@
 
 NetworkServiceLoader::NetworkServiceLoader() {
 }
 
 NetworkServiceLoader::~NetworkServiceLoader() {
 }
 
 void NetworkServiceLoader::LoadService(
     ServiceManager* manager,
     const GURL& url,
-    ScopedMessagePipeHandle shell_handle) {
+    scoped_refptr<LoadServiceCallbacks> callbacks) {
+  ScopedMessagePipeHandle shell_handle = callbacks->RegisterApplication();
+  if (!shell_handle.is_valid())
+    return;
+
   uintptr_t key = reinterpret_cast<uintptr_t>(manager);
   if (apps_.find(key) == apps_.end()) {
     scoped_ptr<ApplicationImpl> app(
         new ApplicationImpl(this, shell_handle.Pass()));
     apps_.add(key, app.Pass());
   }
 }
 
 void NetworkServiceLoader::OnServiceError(ServiceManager* manager,
                                           const GURL& url) {
@@ skipping 11 matching lines @@
   return true;
 }
 
 void NetworkServiceLoader::Create(ApplicationConnection* connection,
                                   InterfaceRequest<NetworkService> request) {
   BindToRequest(new NetworkServiceImpl(connection, context_.get()), &request);
 }
 
 }  // namespace shell
 }  // namespace mojo