Use ShellPtr type in ApplicationLoader instead of untyped handles

shell/external_application_listener_unittest.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 "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/threading/thread.h"
@@ skipping 15 matching lines @@
 namespace mojo {
 namespace shell {
 
 class NotAnApplicationLoader : public ApplicationLoader {
  public:
   NotAnApplicationLoader() {}
   ~NotAnApplicationLoader() override {}
 
   void Load(ApplicationManager* application_manager,
             const GURL& url,
-            ScopedMessagePipeHandle shell_handle,
+            ShellPtr shell,
             LoadCallback callback) override {
     NOTREACHED();
   }
 
   void OnApplicationError(ApplicationManager* manager,
                           const GURL& url) override {
     NOTREACHED();
   }
 };
 
@@ skipping 194 matching lines @@
   run_loop_.Run();
 
   // The apps need to be destroyed on the thread where they did socket stuff.
   io_thread_.task_runner()->PostTask(
       FROM_HERE, base::Bind(&DestroyOnIOThread, base::Passed(&supersweet_app),
                             base::Passed(&awesome_app)));
 }
 
 }  // namespace shell
 }  // namespace mojo