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

ui/events/x/events_x_utils.cc

Index: ui/events/x/events_x_utils.cc
diff --git a/ui/events/x/events_x_utils.cc b/ui/events/x/events_x_utils.cc
index 0e4f9a2669f432e4ded9814a1d7d0f9da08bcee6..704229d7ad9cd444c5395cfb6c6fe0d8b2ec2224 100644
--- a/ui/events/x/events_x_utils.cc
+++ b/ui/events/x/events_x_utils.cc
@@ -312,11 +312,11 @@ std::unique_ptr<base::TickClock> g_tick_clock;
 
 // Takes Xlib Time and returns a time delta that is immune to timer rollover.
 // This function is not thread safe as we do not use a lock.
-base::TimeDelta TimeDeltaFromXEventTime(Time timestamp) {
+base::TimeTicks TimeTicksFromXEventTime(Time timestamp) {
   int64_t timestamp64 = timestamp;
 
   if (!timestamp)
-    return base::TimeDelta();
+    return base::TimeTicks();
 
   // If this is the first event that we get, assume the time stamp roll-over
   // might have happened before the process was started.
@@ -329,7 +329,8 @@ base::TimeDelta TimeDeltaFromXEventTime(Time timestamp) {
 
   g_last_seen_timestamp_ms = timestamp64;
   if (!had_recent_rollover)
-    return base::TimeDelta::FromMilliseconds(g_rollover_ms + timestamp);
+    return base::TimeTicks() +
+           base::TimeDelta::FromMilliseconds(g_rollover_ms + timestamp);
 
   DCHECK(timestamp64 <= UINT32_MAX)
       << "X11 Time does not roll over 32 bit, the below logic is likely wrong";
@@ -345,7 +346,7 @@ base::TimeDelta TimeDeltaFromXEventTime(Time timestamp) {
   DCHECK(delta < 60 * 1000 || g_tick_clock)
       << "Unexpected X11 event time, now: " << now_ticks
       << " event at: " << timestamp;
-  return base::TimeDelta::FromMilliseconds(now_ms - delta);
+  return base::TimeTicks() + base::TimeDelta::FromMilliseconds(now_ms - delta);
 }
 
 }  // namespace
@@ -522,41 +523,43 @@ int EventFlagsFromXEvent(const XEvent& xev) {
   return 0;
 }
 
-base::TimeDelta EventTimeFromXEvent(const XEvent& xev) {
+base::TimeTicks EventTimeFromXEvent(const XEvent& xev) {
   switch (xev.type) {
     case KeyPress:
     case KeyRelease:
-      return TimeDeltaFromXEventTime(xev.xkey.time);
+      return TimeTicksFromXEventTime(xev.xkey.time);
     case ButtonPress:
     case ButtonRelease:
-      return TimeDeltaFromXEventTime(xev.xbutton.time);
+      return TimeTicksFromXEventTime(xev.xbutton.time);
       break;
     case MotionNotify:
-      return TimeDeltaFromXEventTime(xev.xmotion.time);
+      return TimeTicksFromXEventTime(xev.xmotion.time);
       break;
     case EnterNotify:
     case LeaveNotify:
-      return TimeDeltaFromXEventTime(xev.xcrossing.time);
+      return TimeTicksFromXEventTime(xev.xcrossing.time);
       break;
     case GenericEvent: {
       double start, end;
       double touch_timestamp;
       if (GetGestureTimes(xev, &start, &end)) {
         // If the driver supports gesture times, use them.
-        return base::TimeDelta::FromMicroseconds(end * 1000000);
+        return base::TimeTicks() +
+               base::TimeDelta::FromMicroseconds(end * 1000000);
       } else if (DeviceDataManagerX11::GetInstance()->GetEventData(
                      xev, DeviceDataManagerX11::DT_TOUCH_RAW_TIMESTAMP,
                      &touch_timestamp)) {
-        return base::TimeDelta::FromMicroseconds(touch_timestamp * 1000000);
+        return base::TimeTicks() +
+               base::TimeDelta::FromMicroseconds(touch_timestamp * 1000000);
       } else {
         XIDeviceEvent* xide = static_cast<XIDeviceEvent*>(xev.xcookie.data);
-        return TimeDeltaFromXEventTime(xide->time);
+        return TimeTicksFromXEventTime(xide->time);
       }
       break;
     }
   }
   NOTREACHED();
-  return base::TimeDelta();
+  return base::TimeTicks();
 }
 
 gfx::Point EventLocationFromXEvent(const XEvent& xev) {