Makes DesktopWindowTreeHostXxx to dispatch key event to InputMethod.

ash/host/ash_window_tree_host_x11.cc

Index: ash/host/ash_window_tree_host_x11.cc
diff --git a/ash/host/ash_window_tree_host_x11.cc b/ash/host/ash_window_tree_host_x11.cc
index 9ac9d15f7837c30799822d947429840a0c1b5092..93c4d5c37a2029ffe7726df0a903d2a1edb396b5 100644
--- a/ash/host/ash_window_tree_host_x11.cc
+++ b/ash/host/ash_window_tree_host_x11.cc
@@ -239,16 +239,13 @@ void AshWindowTreeHostX11::TranslateAndDispatchLocatedEvent(
 bool AshWindowTreeHostX11::DispatchKeyEventPostIME(const ui::KeyEvent& event) {
   ui::KeyEvent event_copy(event);
   input_method_handler()->SetPostIME(true);
-  ui::EventSource::DeliverEventToProcessor(&event_copy);
+  ui::EventDispatchDetails details =
+      event_processor()->OnEventFromSource(&event_copy);
+  DCHECK(!details.dispatcher_destroyed);

[sadrul, 2015/07/19 01:07:30]

Do these DCHECK()s not trip when, for example, ctrl+shift+Q is pressed to
terminate the shell?

[Shu Chen, 2015/07/20 05:46:09]

Done. I've changed it to use ignore_result().

[sadrul, 2015/07/22 01:04:38]

This should either be a DCHECK, or an early return if dispatcher_destroyed
(otherwise the next line can do a uaF)

[Shu Chen, 2015/07/22 01:19:06]

Done.

   input_method_handler()->SetPostIME(false);
   return event_copy.stopped_propagation();
 }
 
-ui::EventDispatchDetails AshWindowTreeHostX11::DeliverEventToProcessor(
-    ui::Event* event) {
-  return ui::EventSource::DeliverEventToProcessor(event);
-}
-
 #if defined(OS_CHROMEOS)
 void AshWindowTreeHostX11::SetCrOSTapPaused(bool state) {
   if (!ui::IsXInput2Available())