Use SingleThreadTaskRunner instead of MessageLoopProxy in remoting/host.

remoting/host/desktop_environment.cc

Index: remoting/host/desktop_environment.cc
diff --git a/remoting/host/desktop_environment.cc b/remoting/host/desktop_environment.cc
index 7eb755de6ac94c5f21f653af364c57a3832aed11..668fbb86ea2b428440051478b58cc095c247445d 100644
--- a/remoting/host/desktop_environment.cc
+++ b/remoting/host/desktop_environment.cc
@@ -21,8 +21,8 @@ scoped_ptr<DesktopEnvironment> DesktopEnvironment::Create(
     ChromotingHostContext* context) {
   scoped_ptr<Capturer> capturer(Capturer::Create());
   scoped_ptr<EventExecutor> event_executor = EventExecutor::Create(
-      context->desktop_message_loop()->message_loop_proxy(),
-      context->ui_message_loop(), capturer.get());
+      context->desktop_task_runner(), context->ui_task_runner(),
+      capturer.get());
 
   if (capturer.get() == NULL || event_executor.get() == NULL) {
     LOG(ERROR) << "Unable to create DesktopEnvironment";
@@ -40,8 +40,8 @@ scoped_ptr<DesktopEnvironment> DesktopEnvironment::CreateForService(
     ChromotingHostContext* context) {
   scoped_ptr<Capturer> capturer(Capturer::Create());
   scoped_ptr<EventExecutor> event_executor = EventExecutor::Create(
-      context->desktop_message_loop()->message_loop_proxy(),
-      context->ui_message_loop(), capturer.get());
+      context->desktop_task_runner(), context->ui_task_runner(),
+      capturer.get());
 
   if (capturer.get() == NULL || event_executor.get() == NULL) {
     LOG(ERROR) << "Unable to create DesktopEnvironment";