Touchpad scroll latching enabled for Mac behind flag.

cc/input/scroll_state_data.cc

 // Copyright 2015 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 "cc/input/scroll_state_data.h"
 #include "cc/trees/scroll_node.h"
 
 namespace cc {
 
 ScrollStateData::ScrollStateData()
     : delta_x(0),
       delta_y(0),
       position_x(0),
       position_y(0),
       velocity_x(0),
       velocity_y(0),
       is_beginning(false),
       is_in_inertial_phase(false),
       is_ending(false),
+      may_precede_fling(false),
       should_propagate(false),
       from_user_input(false),
       delta_consumed_for_scroll_sequence(false),
       is_direct_manipulation(false),
       delta_granularity(0),
       caused_scroll_x(false),
       caused_scroll_y(false),
       current_native_scrolling_node_(nullptr) {}
 
 ScrollStateData::ScrollStateData(const ScrollStateData& other) = default;
@@ skipping 14 matching lines @@
   return current_native_scrolling_element_;
 }
 
 void ScrollStateData::set_current_native_scrolling_element(
     ElementId element_id) {
   current_native_scrolling_element_ = element_id;
   current_native_scrolling_node_ = nullptr;
 }
 
 }  // namespace cc