Run event executor on the ui thread to remove the need to explicitly XFlush() the XTest calls.

remoting/host/chromoting_host.cc

Index: remoting/host/chromoting_host.cc
diff --git a/remoting/host/chromoting_host.cc b/remoting/host/chromoting_host.cc
index 317e5b083c32ce3a0844d44de35f8eda2b53a912..41eb5a01f33adfb3ffd569aad43699cdc5455f03 100644
--- a/remoting/host/chromoting_host.cc
+++ b/remoting/host/chromoting_host.cc
@@ -35,7 +35,7 @@ namespace remoting {
 ChromotingHost* ChromotingHost::Create(ChromotingHostContext* context,
                                        MutableHostConfig* config) {
   Capturer* capturer = Capturer::Create(context->main_message_loop());
-  InputStub* input_stub = CreateEventExecutor(context->main_message_loop(),
+  InputStub* input_stub = CreateEventExecutor(context->ui_message_loop(),
                                               capturer);
   return Create(context, config, capturer, input_stub);
 }