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

cc/trees/layer_tree_host_impl.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_TREES_LAYER_TREE_HOST_IMPL_H_
 #define CC_TREES_LAYER_TREE_HOST_IMPL_H_
 
 #include <stddef.h>
 
 #include <bitset>
@@ skipping 153 matching lines @@
   void BindToClient(InputHandlerClient* client) override;
   InputHandler::ScrollStatus ScrollBegin(
       ScrollState* scroll_state,
       InputHandler::ScrollInputType type) override;
   InputHandler::ScrollStatus RootScrollBegin(
       ScrollState* scroll_state,
       InputHandler::ScrollInputType type) override;
   ScrollStatus ScrollAnimatedBegin(const gfx::Point& viewport_point) override;
   InputHandler::ScrollStatus ScrollAnimated(
       const gfx::Point& viewport_point,
-      const gfx::Vector2dF& scroll_delta) override;
+      const gfx::Vector2dF& scroll_delta,
+      base::TimeDelta delayed_by = base::TimeDelta()) override;
   void ApplyScroll(ScrollNode* scroll_node, ScrollState* scroll_state);
   InputHandlerScrollResult ScrollBy(ScrollState* scroll_state) override;
   bool ScrollVerticallyByPage(const gfx::Point& viewport_point,
                               ScrollDirection direction) override;
   void RequestUpdateForSynchronousInputHandler() override;
   void SetSynchronousInputHandlerRootScrollOffset(
       const gfx::ScrollOffset& root_offset) override;
   void ScrollEnd(ScrollState* scroll_state) override;
   InputHandler::ScrollStatus FlingScrollBegin() override;
   void MouseMoveAt(const gfx::Point& viewport_point) override;
@@ skipping 410 matching lines @@
   }
 
   InputHandler::ScrollStatus TryScroll(const gfx::PointF& screen_space_point,
                                        InputHandler::ScrollInputType type,
                                        const ScrollTree& scroll_tree,
                                        ScrollNode* scroll_node) const;
 
   // Returns true if a scroll offset animation is created and false if we scroll
   // by the desired amount without an animation.
   bool ScrollAnimationCreate(ScrollNode* scroll_node,
-                             const gfx::Vector2dF& scroll_amount);
+                             const gfx::Vector2dF& scroll_amount,
+                             base::TimeDelta delayed_by);
 
   void SetLayerTreeMutator(std::unique_ptr<LayerTreeMutator> mutator);
   LayerTreeMutator* mutator() { return mutator_.get(); }
 
   void ClearCurrentlyScrollingLayerForTesting() {
     ClearCurrentlyScrollingLayer();
   }
 
  protected:
   LayerTreeHostImpl(
@@ skipping 89 matching lines @@
   void ClearUIResources();
 
   void NotifySwapPromiseMonitorsOfSetNeedsRedraw();
   void NotifySwapPromiseMonitorsOfForwardingToMainThread();
 
   void UpdateRootLayerStateForSynchronousInputHandler();
 
   void ScrollAnimationAbort(LayerImpl* layer_impl);
 
   bool ScrollAnimationUpdateTarget(ScrollNode* scroll_node,
-                                   const gfx::Vector2dF& scroll_delta);
+                                   const gfx::Vector2dF& scroll_delta,
+                                   base::TimeDelta delayed_by);
 
   void SetCompositorContextVisibility(bool is_visible);
   void SetWorkerContextVisibility(bool is_visible);
 
   using UIResourceMap = std::unordered_map<UIResourceId, UIResourceData>;
   UIResourceMap ui_resource_map_;
 
   // Resources that were evicted by EvictAllUIResources. Resources are removed
   // from this when they are touched by a create or destroy from the UI resource
   // request queue.
@@ skipping 127 matching lines @@
 
   std::unique_ptr<PendingTreeDurationHistogramTimer>
       pending_tree_duration_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_IMPL_H_