Keep track of coalesced events in main thread event queue

content/renderer/render_view_impl.cc

Index: content/renderer/render_view_impl.cc
diff --git a/content/renderer/render_view_impl.cc b/content/renderer/render_view_impl.cc
index cc597bd1005feb03373f86ae3d7fa3b5266b330f..6b4072e2cfa40e5ffd7f1b3d87998c9cbccf6630 100644
--- a/content/renderer/render_view_impl.cc
+++ b/content/renderer/render_view_impl.cc
@@ -2715,6 +2715,7 @@ void RenderViewImpl::UpdateWebViewWithDeviceScaleFactor() {
 
 void RenderViewImpl::OnDiscardInputEvent(
     const blink::WebInputEvent* input_event,
+    const std::vector<const blink::WebInputEvent*>& coalescedEvents,

[dcheng, 2017/01/23 19:38:58]

Though I'm a little surprised that this doesn't seem to be used?

[Navid Zolghadr, 2017/01/23 21:42:04]

I believe there are some paths that may still need some plumbing. I just didn't
want to do it all in one patch. So far this CL at least addresses the portion of
the usecase we needed. More of the plumbing can be done later when we face the
need in different scenarios.

[dcheng, 2017/01/23 21:46:26]

Might be better to just add it when it's needed? I think it's needed everywhere
else, and if we find this plumbing is missing later, it's easy enough to add it
back.

     const ui::LatencyInfo& latency_info,
     InputEventDispatchType dispatch_type) {
   if (!input_event || (dispatch_type != DISPATCH_TYPE_BLOCKING &&