Revert of Remove enable/disable wheel gestures setting.

content/browser/renderer_host/input/mouse_wheel_event_queue.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 CONTENT_BROWSER_RENDERER_HOST_INPUT_MOUSE_WHEEL_EVENT_QUEUE_H_
 #define CONTENT_BROWSER_RENDERER_HOST_INPUT_MOUSE_WHEEL_EVENT_QUEUE_H_
 
 #include <deque>
 
 #include "base/time/time.h"
@@ skipping 29 matching lines @@
 
 // A queue for throttling and coalescing mouse wheel events.
 class CONTENT_EXPORT MouseWheelEventQueue {
  public:
   // The |client| must outlive the MouseWheelEventQueue. |send_gestures|
   // indicates whether mouse wheel events should generate
   // Scroll[Begin|Update|End] on unhandled acknowledge events.
   // |scroll_transaction_ms| is the duration in which the
   // ScrollEnd should be sent after a ScrollUpdate.
   MouseWheelEventQueue(MouseWheelEventQueueClient* client,
+                       bool send_gestures,
                        int64_t scroll_transaction_ms);
 
   ~MouseWheelEventQueue();
 
   // Adds an event to the queue. The event may be coalesced with previously
   // queued events (e.g. consecutive mouse-wheel events can be coalesced into a
   // single mouse-wheel event). The event may also be immediately forwarded to
   // the renderer (e.g. when there are no other queued mouse-wheel event).
   void QueueEvent(const MouseWheelEventWithLatencyInfo& event);
 
@@ skipping 30 matching lines @@
   WheelEventQueue wheel_queue_;
   std::unique_ptr<QueuedWebMouseWheelEvent> event_sent_for_gesture_ack_;
 
   // True if a non-synthetic GSB needs to be sent before a GSU is sent.
   bool needs_scroll_begin_;
 
   // True if a non-synthetic GSE needs to be sent because a non-synthetic
   // GSB has been sent in the past.
   bool needs_scroll_end_;
 
+  bool send_gestures_;
   int64_t scroll_transaction_ms_;
   blink::WebGestureDevice scrolling_device_;
 
   DISALLOW_COPY_AND_ASSIGN(MouseWheelEventQueue);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_MOUSE_WHEEL_EVENT_QUEUE_H_