Support vsync-aligned wheel event dispatch

content/browser/renderer_host/input/input_router_config_helper.cc

 // Copyright 2014 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/input/input_router_config_helper.h"
 
 #include "base/command_line.h"
+#include "cc/base/switches.h"
 #include "content/public/common/content_switches.h"
 #include "ui/events/gesture_detection/gesture_configuration.h"
 #include "ui/events/gesture_detection/gesture_detector.h"
 
 namespace content {
 namespace {
 
 // Default time allowance for the touch ack delay before the touch sequence is
 // cancelled, depending on whether the site has a mobile-friendly viewport.
 // Note that these constants are effective only when the timeout is supported.
@@ skipping 45 matching lines @@
 
   return config;
 }
 
 }  // namespace
 
 InputRouterImpl::Config GetInputRouterConfigForPlatform() {
   InputRouterImpl::Config config;
   config.gesture_config = GetGestureEventQueueConfig();
   config.touch_config = GetTouchEventQueueConfig();
+#if !defined(OS_ANDROID)
+  config.buffer_wheel_events_until_flush =
+      base::CommandLine::ForCurrentProcess()->HasSwitch(
+          cc::switches::kEnableBeginFrameScheduling);
+#else
+  config.buffer_wheel_events_until_flush = false;
+#endif
   return config;
 }
 
 }  // namespace content