Showing Gloweffect correctly during fling on mainthread.

content/renderer/render_widget.cc

Index: content/renderer/render_widget.cc
diff --git a/content/renderer/render_widget.cc b/content/renderer/render_widget.cc
index c512d41fce1f9ef2586cbe2d416d3b84e793210e..06ddb9a862ecb62b4f8e1b3c152e643bb223d997 100644
--- a/content/renderer/render_widget.cc
+++ b/content/renderer/render_widget.cc
@@ -166,6 +166,11 @@ int64 GetEventLatencyMicros(const WebInputEvent& event, base::TimeTicks now) {
       .ToInternalValue();
 }
 
+// TODO(sataya.m): Remove this api once http://crbug.com/499743 is fixed.
+gfx::Vector2dF ToClientScrollIncrement(const blink::WebFloatSize& increment) {

[jdduke (slow), 2015/06/12 14:53:16]

Let's just inline this function and the comment, I don't think we want it to be
used by code other than overscroll.

[MuVen, 2015/06/12 15:08:04]

Done.

+  return gfx::Vector2dF(-increment.width, -increment.height);
+}
+
 void LogInputEventLatencyUma(const WebInputEvent& event, base::TimeTicks now) {
   UMA_HISTOGRAM_CUSTOM_COUNTS(
       "Event.AggregatedLatency.Renderer2",
@@ -2228,8 +2233,7 @@ void RenderWidget::didOverscroll(
       accumulatedRootOverScroll.width, accumulatedRootOverScroll.height);
   params.latest_overscroll_delta =
       gfx::Vector2dF(unusedDelta.width, unusedDelta.height);
-  params.current_fling_velocity =
-      gfx::Vector2dF(velocity.width, velocity.height);
+  params.current_fling_velocity = ToClientScrollIncrement(velocity);
   params.causal_event_viewport_point = gfx::PointF(position.x, position.y);
   Send(new InputHostMsg_DidOverscroll(routing_id_, params));
 }