Set the unique_event_id when converting from TouchEvent to WebTouchEvent

ui/events/gesture_detection/motion_event_generic_unittest.cc

Index: ui/events/gesture_detection/motion_event_generic_unittest.cc
diff --git a/ui/events/gesture_detection/motion_event_generic_unittest.cc b/ui/events/gesture_detection/motion_event_generic_unittest.cc
index a67646b24f57a5f94a574cada63b75be91afc4d5..b6f64deebff45d460c870ce84edf8f9f93980ec0 100644
--- a/ui/events/gesture_detection/motion_event_generic_unittest.cc
+++ b/ui/events/gesture_detection/motion_event_generic_unittest.cc
@@ -17,6 +17,10 @@ TEST(MotionEventGenericTest, Basic) {
   EXPECT_EQ(0U, event.GetHistorySize());
   EXPECT_EQ(event_time, event.GetEventTime());
 
+  DCHECK_NE(0U, event.GetUniqueEventId());
+  event.set_unique_event_id(123456U);
+  EXPECT_EQ(123456U, event.GetUniqueEventId());
+
   event.PushPointer(PointerProperties(8.3f, 4.7f, 0.9f));
   ASSERT_EQ(2U, event.GetPointerCount());
   EXPECT_EQ(8.3f, event.GetX(1));
@@ -27,8 +31,8 @@ TEST(MotionEventGenericTest, Basic) {
   EXPECT_EQ(2.3f, event.GetX(2));
   EXPECT_EQ(-3.7f, event.GetY(2));
 
-  event.set_id(1);
-  EXPECT_EQ(1, event.GetId());
+  event.pointer(0).id = 3;
+  EXPECT_EQ(3, event.GetPointerId(0));
 
   event.set_action(MotionEvent::ACTION_POINTER_DOWN);
   EXPECT_EQ(MotionEvent::ACTION_POINTER_DOWN, event.GetAction());
@@ -78,7 +82,6 @@ TEST(MotionEventGenericTest, Clone) {
   MotionEventGeneric event(MotionEvent::ACTION_DOWN,

[jdduke (slow), 2015/04/27 17:11:07]

Can you make sure the event id is cloned for Clone(), and that it's different
for Cancel()?

[lanwei, 2015/04/28 16:24:35]

Done.

                            base::TimeTicks::Now(),
                            PointerProperties(8.3f, 4.7f, 2.f));
-  event.set_id(1);
   event.set_button_state(MotionEvent::BUTTON_PRIMARY);
 
   scoped_ptr<MotionEvent> clone = event.Clone();
@@ -110,7 +113,6 @@ TEST(MotionEventGenericTest, Cancel) {
   MotionEventGeneric event(MotionEvent::ACTION_UP,
                            base::TimeTicks::Now(),
                            PointerProperties(8.7f, 4.3f, 1.f));
-  event.set_id(2);
   event.set_button_state(MotionEvent::BUTTON_SECONDARY);
 
   scoped_ptr<MotionEvent> cancel = event.Cancel();