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

content/browser/renderer_host/ui_events_helper.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/renderer_host/ui_events_helper.h"
 
 #include <stdint.h>
 
 #include "base/memory/ptr_util.h"
 #include "content/common/input/web_touch_event_traits.h"
@@ skipping 72 matching lines @@
                            point.radius_x, point.radius_y, point.force),
         flags, point.rotation_angle);
     uievent->set_location_f(location);
     uievent->set_root_location_f(location);
     uievent->set_latency(touch_with_latency.latency);
     list->push_back(std::move(uievent));
   }
   return true;
 }
 
+bool InputEventAckStateIsSetNonBlocking(InputEventAckState ack_state) {
+  switch (ack_state) {
+    case INPUT_EVENT_ACK_STATE_SET_NON_BLOCKING:
+    case INPUT_EVENT_ACK_STATE_SET_NON_BLOCKING_DUE_TO_FLING:
+      return true;
+    default:
+      return false;
+  }
+}
+
 }  // namespace content