chrome: Remove use of MessageLoopProxy and deprecated MessageLoop APIs

chrome/app_shim/chrome_main_app_mode_mac.mm

Index: chrome/app_shim/chrome_main_app_mode_mac.mm
diff --git a/chrome/app_shim/chrome_main_app_mode_mac.mm b/chrome/app_shim/chrome_main_app_mode_mac.mm
index ca3d271ebc9a3731081c8bc8afcb088b082f342e..98630a62270e229400f68b10a4c4a1c46f3a0b10 100644
--- a/chrome/app_shim/chrome_main_app_mode_mac.mm
+++ b/chrome/app_shim/chrome_main_app_mode_mac.mm
@@ -211,10 +211,8 @@ void AppShimController::Init() {
 void AppShimController::CreateChannelAndSendLaunchApp(
     const base::FilePath& socket_path) {
   IPC::ChannelHandle handle(socket_path.value());
-  channel_ = IPC::ChannelProxy::Create(handle,
-                                       IPC::Channel::MODE_NAMED_CLIENT,
-                                       this,
-                                       g_io_thread->message_loop_proxy().get());
+  channel_ = IPC::ChannelProxy::Create(handle, IPC::Channel::MODE_NAMED_CLIENT,
+                                       this, g_io_thread->task_runner().get());
 
   bool launched_by_chrome = base::CommandLine::ForCurrentProcess()->HasSwitch(
       app_mode::kLaunchedByChromeProcessId);