Introduce IPC::ChannelProxy::Create*() and IPC::SynChannel::Create*()

apps/app_shim/chrome_main_app_mode_mac.mm

 // Copyright 2013 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.
 
 // On Mac, one can't make shortcuts with command-line arguments. Instead, we
 // produce small app bundles which locate the Chromium framework and load it,
 // passing the appropriate data. This is the entry point into the framework for
 // those app bundles.
 
 #import <Cocoa/Cocoa.h>
@@ skipping 196 matching lines @@
   }
 
   app_mode::VerifySocketPermissions(socket_path);
 
   CreateChannelAndSendLaunchApp(socket_path);
 }
 
 void AppShimController::CreateChannelAndSendLaunchApp(
     const base::FilePath& socket_path) {
   IPC::ChannelHandle handle(socket_path.value());
-  channel_.reset(
-      new IPC::ChannelProxy(handle,
-                            IPC::Channel::MODE_NAMED_CLIENT,
-                            this,
-                            g_io_thread->message_loop_proxy().get()));
+  channel_ = IPC::ChannelProxy::CreateNamedClient(
+      handle, this, g_io_thread->message_loop_proxy().get());
 
   bool launched_by_chrome =
       CommandLine::ForCurrentProcess()->HasSwitch(
           app_mode::kLaunchedByChromeProcessId);
   apps::AppShimLaunchType launch_type = launched_by_chrome ?
           apps::APP_SHIM_LAUNCH_REGISTER_ONLY : apps::APP_SHIM_LAUNCH_NORMAL;
 
   [delegate_ setController:this];
 
   std::vector<base::FilePath> files;
@@ skipping 434 matching lines @@
     // minute.
     main_message_loop.PostTask(
         FROM_HERE,
         base::Bind(&AppShimController::Init,
                    base::Unretained(&controller)));
   }
 
   main_message_loop.Run();
   return 0;
 }