Revert of Run smooth scroll animations on the compositor when possible

third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h

Index: third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h
diff --git a/third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h b/third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h
index 5926f865208fdb2493e96fa0f026c8ac81956a0f..3503b7f1a0b5e0a8f8009496307d7a62f18c5035 100644
--- a/third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h
+++ b/third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h
@@ -35,7 +35,6 @@
 #include "platform/PlatformWheelEvent.h"
 #include "platform/geometry/FloatSize.h"
 #include "platform/heap/Handle.h"
-#include "platform/scroll/ScrollAnimatorCompositorCoordinator.h"
 #include "platform/scroll/ScrollTypes.h"
 #include "wtf/Forward.h"
 
@@ -44,9 +43,8 @@
 class FloatPoint;
 class ScrollableArea;
 class Scrollbar;
-class WebCompositorAnimationTimeline;
 
-class PLATFORM_EXPORT ScrollAnimatorBase : public ScrollAnimatorCompositorCoordinator {
+class PLATFORM_EXPORT ScrollAnimatorBase : public NoBaseWillBeGarbageCollectedFinalized<ScrollAnimatorBase> {
 public:
     static PassOwnPtrWillBeRawPtr<ScrollAnimatorBase> create(ScrollableArea*);
 
@@ -63,6 +61,8 @@
 
     virtual void scrollToOffsetWithoutAnimation(const FloatPoint&);
 
+    ScrollableArea* scrollableArea() const { return m_scrollableArea; }
+
     virtual void setIsActive() { }
 
 #if OS(MACOSX)
@@ -76,14 +76,9 @@
     // area.
     virtual float computeDeltaToConsume(ScrollbarOrientation, float pixelDelta) const;
 
-
-    // ScrollAnimatorCompositorCoordinator implementation.
-    ScrollableArea* scrollableArea() const override { return m_scrollableArea; }
-    void tickAnimation(double monotonicTime) override { };
-    void cancelAnimation() override { }
-    void updateCompositorAnimations() override { };
-    void notifyCompositorAnimationFinished(int groupId) override { };
-    void layerForCompositedScrollingDidChange(WebCompositorAnimationTimeline*) override { };
+    virtual void cancelAnimations() { }
+    virtual void serviceScrollAnimations() { }
+    virtual bool hasRunningAnimation() const { return false; }
 
     virtual void contentAreaWillPaint() const { }
     virtual void mouseEnteredContentArea() const { }