PlatformEventDispatcher::DispatchEvent() should return a PostDispatchAction

ui/aura/window_tree_host_x11.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/aura/window_tree_host_x11.h"
 
 #include <strings.h>
 #include <X11/cursorfont.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/extensions/Xrandr.h>
@@ skipping 302 matching lines @@
   DestroyCompositor();
   DestroyDispatcher();
   XDestroyWindow(xdisplay_, xwindow_);
 }
 
 bool WindowTreeHostX11::CanDispatchEvent(const ui::PlatformEvent& event) {
   ::Window target = FindEventTarget(event);
   return target == xwindow_ || target == x_root_window_;
 }
 
-uint32_t WindowTreeHostX11::DispatchEvent(const ui::PlatformEvent& event) {
+ui::PostDispatchAction WindowTreeHostX11::DispatchEvent(
+    const ui::PlatformEvent& event) {
   XEvent* xev = event;
   if (FindEventTarget(xev) == x_root_window_) {
     if (xev->type == GenericEvent)
       DispatchXI2Event(xev);
     return ui::POST_DISPATCH_NONE;
   }
 
   if (xev->type == MotionNotify) {
     // Discard all but the most recent motion event that targets the same
     // window with unchanged state.
@@ skipping 393 matching lines @@
 }
 
 namespace test {
 
 void SetUseOverrideRedirectWindowByDefault(bool override_redirect) {
   default_override_redirect = override_redirect;
 }
 
 }  // namespace test
 }  // namespace aura