Refactor MessagePumpX to dispatch events inside of the source Dispatch function.

base/message_pump_gtk.cc

Index: base/message_pump_gtk.cc
diff --git a/base/message_pump_gtk.cc b/base/message_pump_gtk.cc
index e1cb7f65c4af05e9d3d09ac5db3a144df0c26a07..96fb082bbb8248e6986b94a6708944ec095f9630 100644
--- a/base/message_pump_gtk.cc
+++ b/base/message_pump_gtk.cc
@@ -36,11 +36,6 @@ Display* MessagePumpGtk::GetDefaultXDisplay() {
   return display ? GDK_DISPLAY_XDISPLAY(display) : NULL;
 }
 
-bool MessagePumpGtk::RunOnce(GMainContext* context, bool block) {
-  // g_main_context_iteration returns true if events have been dispatched.
-  return g_main_context_iteration(context, block);
-}
-
 void MessagePumpGtk::WillProcessEvent(GdkEvent* event) {
   FOR_EACH_OBSERVER(MessagePumpObserver, observers(), WillProcessEvent(event));
 }