Let gesture carry microseconds timestamp

We are converting gesture's timestamp to microseconds at many
places (e.g. for latency measure). So let's not truncate the
timestamp to milliseconds level when creating the event.

BUG=243443
TEST=None.

Review URL: https://chromiumcodereview.appspot.com/16159007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@202773 0039d316-1c4b-4281-b951-d872f2087c98

ui/base/gestures/gesture_sequence.cc

@@ -646,9 +646,11 @@ GestureEvent* GestureSequence::CreateGestureEvent(
   GestureEventDetails gesture_details(details);
   gesture_details.set_touch_points(point_count_);
   gesture_details.set_bounding_box(bounding_box_);
+  base::TimeDelta time_stamp =
+      base::TimeDelta::FromMicroseconds(timestamp.ToDoubleT() * 1000000);
   return new GestureEvent(gesture_details.type(), location.x(), location.y(),
-      flags, base::TimeDelta::FromMilliseconds(timestamp.ToDoubleT() * 1000),
-      gesture_details, touch_id_bitmask);
+                          flags, time_stamp, gesture_details,
+                          touch_id_bitmask);
 }
 
 void GestureSequence::AppendTapDownGestureEvent(const GesturePoint& point,