Make touch events uncancelable during fling when they are on the current active scroll layer

cc/input/event_listener_properties.h

 // Copyright 2016 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.
 
 #ifndef CC_INPUT_EVENT_LISTENER_PROPERTIES_H_
 #define CC_INPUT_EVENT_LISTENER_PROPERTIES_H_
 
 namespace cc {
 
 enum class EventListenerClass {
   // This value includes "touchstart", "touchmove", and "pointer" events.
   kTouchStartOrMove,
   // This value includes "wheel" and "mousewheel" events.
   kMouseWheel,
   // This value includes "touchend" and "touchcancel" events.
   kTouchEndOrCancel,
   kNumClasses
 };
 
 enum class EventListenerProperties {
   kNone,
   kPassive,
   kBlocking,
   kBlockingAndPassive,
+  kBlockingAndPassiveDueToFling,
   kMax
 };
 
 }  // namespace cc
 
 #endif  // CC_INPUT_EVENT_LISTENER_PROPERTIES_H_