[not for review - epic CL] Adding Elastic+Momentum+Layered scrolling to views::ScrollView

ui/compositor/compositor.h

Index: ui/compositor/compositor.h
diff --git a/ui/compositor/compositor.h b/ui/compositor/compositor.h
index 1fa1bfc02a3efd96cd86b8c0edb6b93bcfbf27b8..4a6edc691b0c4c305c1dbe3487c43b6cc7d5dc29 100644
--- a/ui/compositor/compositor.h
+++ b/ui/compositor/compositor.h
@@ -51,6 +51,7 @@ class TaskGraphRunner;
 
 namespace gfx {
 class Rect;
+class ScrollOffset;
 class Size;
 }
 
@@ -66,6 +67,7 @@ class CompositorVSyncManager;
 class LatencyInfo;
 class Layer;
 class Reflector;
+class UIScrollInputManager;
 class Texture;
 
 const int kCompositorLockTimeoutMs = 67;
@@ -266,6 +268,11 @@ class COMPOSITOR_EXPORT Compositor
   // Gets the visibility of the underlying compositor.
   bool IsVisible();
 
+  // Gets/Sets the scroll offset for the given layer in step with the
+  // cc::InputHandler.
+  gfx::ScrollOffset GetScrollOffsetForLayer(int layer_id) const;
+  bool ScrollLayerTo(int layer_id, const gfx::ScrollOffset& offset);
+
   // The "authoritative" vsync interval, if provided, will override interval
   // reported from 3D context. This is typically the value reported by a more
   // reliable source, e.g, the platform display configuration.
@@ -364,6 +371,10 @@ class COMPOSITOR_EXPORT Compositor
     return surface_id_allocator_.get();
   }
 
+  UIScrollInputManager* scroll_input_manager() {
+    return scroll_input_manager_.get();
+  }
+
  private:
   friend class base::RefCounted<Compositor>;
   friend class CompositorLock;
@@ -406,6 +417,8 @@ class COMPOSITOR_EXPORT Compositor
   LayerAnimatorCollection layer_animator_collection_;
   scoped_refptr<cc::AnimationTimeline> animation_timeline_;
 
+  std::unique_ptr<UIScrollInputManager> scroll_input_manager_;
+
   base::WeakPtrFactory<Compositor> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Compositor);