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

cc/animation/scroll_offset_animations_impl.cc

Index: cc/animation/scroll_offset_animations_impl.cc
diff --git a/cc/animation/scroll_offset_animations_impl.cc b/cc/animation/scroll_offset_animations_impl.cc
index f49bb9d54f7a3e3f32fd9d64241f97be9e593941..122501621db2c8bf64e2be28cd90a8880a19b7eb 100644
--- a/cc/animation/scroll_offset_animations_impl.cc
+++ b/cc/animation/scroll_offset_animations_impl.cc
@@ -36,13 +36,15 @@ ScrollOffsetAnimationsImpl::~ScrollOffsetAnimationsImpl() {
 void ScrollOffsetAnimationsImpl::ScrollAnimationCreate(
     ElementId element_id,
     const gfx::ScrollOffset& target_offset,
-    const gfx::ScrollOffset& current_offset) {
+    const gfx::ScrollOffset& current_offset,
+    base::TimeTicks original_timestamp) {
   std::unique_ptr<ScrollOffsetAnimationCurve> curve =
       ScrollOffsetAnimationCurve::Create(
           target_offset, CubicBezierTimingFunction::CreatePreset(
                              CubicBezierTimingFunction::EaseType::EASE_IN_OUT),
           ScrollOffsetAnimationCurve::DurationBehavior::INVERSE_DELTA);
-  curve->SetInitialValue(current_offset);
+  curve->SetInitialValue(current_offset,
+                         base::TimeTicks::Now() - original_timestamp);
 
   std::unique_ptr<Animation> animation = Animation::Create(
       std::move(curve), AnimationIdProvider::NextAnimationId(),