Change ui::Event::time_stamp from TimeDelta to TimeTicks

ui/events/event_utils.cc

Index: ui/events/event_utils.cc
diff --git a/ui/events/event_utils.cc b/ui/events/event_utils.cc
index 9291a589af5b7dc281714395c9bd61d41a487c54..cf23dbc9e69c2fa92fc5b4b917a824c1be64224f 100644
--- a/ui/events/event_utils.cc
+++ b/ui/events/event_utils.cc
@@ -60,9 +60,8 @@ int RegisterCustomEventType() {
   return ++g_custom_event_types;
 }
 
-base::TimeDelta EventTimeForNow() {
-  return base::TimeDelta::FromInternalValue(
-      base::TimeTicks::Now().ToInternalValue());
+base::TimeTicks EventTimeForNow() {
+  return base::TimeTicks::Now();
 }
 
 bool ShouldDefaultToNaturalScroll() {