MouseWheelEventQueue should respect ScrollBegin/End state from RenderWidgetHost.

content/browser/renderer_host/input/input_router_impl.h

Index: content/browser/renderer_host/input/input_router_impl.h
diff --git a/content/browser/renderer_host/input/input_router_impl.h b/content/browser/renderer_host/input/input_router_impl.h
index 239d0d212c7b724a01f1bb9b6d0eb51401f7c6af..9b02981e02b53aa821ce6b649eb1297b354aef65 100644
--- a/content/browser/renderer_host/input/input_router_impl.h
+++ b/content/browser/renderer_host/input/input_router_impl.h
@@ -116,6 +116,7 @@ class CONTENT_EXPORT InputRouterImpl
   void ForwardGestureEventWithLatencyInfo(
       const blink::WebGestureEvent& gesture_event,
       const ui::LatencyInfo& latency_info) override;
+  bool IsInGestureScroll() const override;

[dtapuska, 2017/04/13 13:39:47]

This is still missing the quantification. Is it in a touchpad or touchscreen
gesture scroll? Or either? I'd expect the later based on the method name.

[wjmaclean, 2017/04/13 14:17:11]

I thought (as I mentioned previously) that since InputRouterImpl is implementing
MouseWheelEventQueueClient, that it would be clear that this is for Touchpad.
However I can explicitly add that to the name.

 
   bool SendMoveCaret(std::unique_ptr<IPC::Message> message);
   bool SendSelectMessage(std::unique_ptr<IPC::Message> message);