Take MT jank into account when animating the scroll offset on CC

ui/events/blink/input_handler_proxy.cc

Index: ui/events/blink/input_handler_proxy.cc
diff --git a/ui/events/blink/input_handler_proxy.cc b/ui/events/blink/input_handler_proxy.cc
index 9b13d93cd2496cb88dec75fdb796d236368319a6..317ff7dcace97f5da0a98ec75945fd459cfbec3b 100644
--- a/ui/events/blink/input_handler_proxy.cc
+++ b/ui/events/blink/input_handler_proxy.cc
@@ -275,12 +275,14 @@ InputHandlerProxy::HandleInputEventWithLatencyInfo(
 
   std::unique_ptr<cc::SwapPromiseMonitor> latency_info_swap_promise_monitor =
       input_handler_->CreateLatencyInfoSwapPromiseMonitor(latency_info);
-  InputHandlerProxy::EventDisposition disposition = HandleInputEvent(event);
+  InputHandlerProxy::EventDisposition disposition =
+      HandleInputEvent(event, latency_info);
   return disposition;
 }
 
 InputHandlerProxy::EventDisposition InputHandlerProxy::HandleInputEvent(
-    const WebInputEvent& event) {
+    const WebInputEvent& event,
+    ui::LatencyInfo* latency_info) {
   DCHECK(input_handler_);
 
   if (FilterInputEventForFlingBoosting(event))
@@ -296,7 +298,7 @@ InputHandlerProxy::EventDisposition InputHandlerProxy::HandleInputEvent(
 
     case WebInputEvent::GestureScrollUpdate:
       return HandleGestureScrollUpdate(
-          static_cast<const WebGestureEvent&>(event));
+          static_cast<const WebGestureEvent&>(event), latency_info);
 
     case WebInputEvent::GestureScrollEnd:
       return HandleGestureScrollEnd(static_cast<const WebGestureEvent&>(event));
@@ -496,7 +498,7 @@ InputHandlerProxy::EventDisposition InputHandlerProxy::ScrollByMouseWheel(
   } else if (ShouldAnimate(wheel_event.hasPreciseScrollingDeltas)) {
     cc::InputHandler::ScrollStatus scroll_status =
         input_handler_->ScrollAnimated(gfx::Point(wheel_event.x, wheel_event.y),
-                                       scroll_delta);
+                                       scroll_delta, nullptr);
 
     RecordMainThreadScrollingReasons(
         blink::WebGestureDeviceTouchpad,
@@ -643,7 +645,8 @@ InputHandlerProxy::EventDisposition InputHandlerProxy::HandleGestureScrollBegin(
 
 InputHandlerProxy::EventDisposition
 InputHandlerProxy::HandleGestureScrollUpdate(
-  const WebGestureEvent& gesture_event) {
+    const WebGestureEvent& gesture_event,
+    ui::LatencyInfo* latency_info) {
 #ifndef NDEBUG
   DCHECK(expect_scroll_update_end_);
 #endif
@@ -657,7 +660,9 @@ InputHandlerProxy::HandleGestureScrollUpdate(
 
   if (ShouldAnimate(gesture_event.data.scrollUpdate.deltaUnits !=
                     blink::WebGestureEvent::ScrollUnits::Pixels)) {
-    switch (input_handler_->ScrollAnimated(scroll_point, scroll_delta).thread) {
+    switch (
+        input_handler_->ScrollAnimated(scroll_point, scroll_delta, latency_info)
+            .thread) {
       case cc::InputHandler::SCROLL_ON_IMPL_THREAD:
         return DID_HANDLE;
       case cc::InputHandler::SCROLL_IGNORED: