Add event trace to DispatchEvent on ozone

ui/aura/window_tree_host_ozone.cc

Index: ui/aura/window_tree_host_ozone.cc
diff --git a/ui/aura/window_tree_host_ozone.cc b/ui/aura/window_tree_host_ozone.cc
index 0b6df97bb1717ac05c277c5fc313570a4c2a2551..1559c243e0b03696dd9da653b945d31c6b7ab332 100644
--- a/ui/aura/window_tree_host_ozone.cc
+++ b/ui/aura/window_tree_host_ozone.cc
@@ -4,6 +4,7 @@
 
 #include "ui/aura/window_tree_host_ozone.h"
 
+#include "base/trace_event/trace_event.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/ozone/public/ozone_platform.h"
 #include "ui/platform_window/platform_window.h"
@@ -81,6 +82,7 @@ void WindowTreeHostOzone::OnDamageRect(const gfx::Rect& damaged_region) {
 }
 
 void WindowTreeHostOzone::DispatchEvent(ui::Event* event) {

[spang, 2015/03/04 00:14:05]

FYI

ash overrides this function. It will not be called with ash.

+  TRACE_EVENT0("input", "WindowTreeHostOzone::DispatchEvent");
   SendEventToProcessor(event);
 }