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

cc/animation/animation_host.h

Index: cc/animation/animation_host.h
diff --git a/cc/animation/animation_host.h b/cc/animation/animation_host.h
index 8f5ff14a725896cf659af1c1e2be403ab2d98cee..46dd9327c69ee25f0a2265a1e7fcde9dba1bed02 100644
--- a/cc/animation/animation_host.h
+++ b/cc/animation/animation_host.h
@@ -143,6 +143,9 @@ class CC_EXPORT AnimationHost {
       const gfx::ScrollOffset& max_scroll_offset,
       base::TimeTicks frame_monotonic_time);
 
+  void ImplOnlyScrollAnimationAdjustDuration(ElementId element_id,
+                                             base::TimeDelta adjustment);
+
   void ScrollAnimationAbort(bool needs_completion);
 
   // This should only be called from the main thread.