[VSync Queue] Plug touch ack to gesture events and flush vsync queue if necessary

ui/chromeos/touch_exploration_controller.cc

Index: ui/chromeos/touch_exploration_controller.cc
diff --git a/ui/chromeos/touch_exploration_controller.cc b/ui/chromeos/touch_exploration_controller.cc
index c756b0a00543de69c3d6f4706118970b726fa3f4..bd0473c6d5db32326eedd59113d65fd011eb9eb4 100644
--- a/ui/chromeos/touch_exploration_controller.cc
+++ b/ui/chromeos/touch_exploration_controller.cc
@@ -197,8 +197,9 @@ ui::EventRewriteStatus TouchExplorationController::RewriteEvent(
   if (gesture_provider_.get()) {
     ui::TouchEvent mutable_touch_event = touch_event;
     if (gesture_provider_->OnTouchEvent(&mutable_touch_event)) {
-      gesture_provider_->OnTouchEventAck(mutable_touch_event.unique_event_id(),
-                                         false);
+      gesture_provider_->OnTouchEventAck(
+          mutable_touch_event.unique_event_id(), false /* event_consumed */,
+          false /* is_source_touch_event_set_non_blocking */);
     }
     ProcessGestureEvents();
   }