Revert of Animations: Port ProgrammaticScrollAnimator to use compositor timelines

Source/core/page/scrolling/ScrollingCoordinator.cpp

Index: Source/core/page/scrolling/ScrollingCoordinator.cpp
diff --git a/Source/core/page/scrolling/ScrollingCoordinator.cpp b/Source/core/page/scrolling/ScrollingCoordinator.cpp
index a334e43f183a72f60289698657e7a65059241b2b..21d9228c1f761e6b57241ab688d372f7e14188f2 100644
--- a/Source/core/page/scrolling/ScrollingCoordinator.cpp
+++ b/Source/core/page/scrolling/ScrollingCoordinator.cpp
@@ -56,7 +56,6 @@
 #include "platform/scroll/ScrollAnimator.h"
 #include "platform/scroll/ScrollbarTheme.h"
 #include "public/platform/Platform.h"
-#include "public/platform/WebCompositorAnimationTimeline.h"
 #include "public/platform/WebCompositorSupport.h"
 #include "public/platform/WebLayerPositionConstraint.h"
 #include "public/platform/WebScrollbarLayer.h"
@@ -94,13 +93,6 @@
     , m_wasFrameScrollable(false)
     , m_lastMainThreadScrollingReasons(0)
 {
-    if (RuntimeEnabledFeatures::compositorAnimationTimelinesEnabled()) {
-        ASSERT(m_page);
-        ASSERT(m_page->mainFrame()->isLocalFrame());
-        ASSERT(Platform::current()->compositorSupport());
-        m_programmaticScrollAnimatorTimeline = adoptPtr(Platform::current()->compositorSupport()->createAnimationTimeline());
-        m_page->chromeClient().attachCompositorAnimationTimeline(m_programmaticScrollAnimatorTimeline.get(), toLocalFrame(m_page->mainFrame()));
-    }
 }
 
 ScrollingCoordinator::~ScrollingCoordinator()
@@ -443,7 +435,7 @@
     if (m_page->settings().rootLayerScrolls() && isForRootLayer(scrollableArea))
         m_page->chromeClient().registerViewportLayers();
 
-    scrollableArea->layerForScrollingDidChange(m_programmaticScrollAnimatorTimeline.get());
+    scrollableArea->layerForScrollingDidChange();
 
     return !!webLayer;
 }
@@ -731,13 +723,6 @@
 void ScrollingCoordinator::willBeDestroyed()
 {
     ASSERT(m_page);
-
-    if (m_programmaticScrollAnimatorTimeline) {
-        ASSERT(m_page->mainFrame()->isLocalFrame());
-        m_page->chromeClient().detachCompositorAnimationTimeline(m_programmaticScrollAnimatorTimeline.get(), toLocalFrame(m_page->mainFrame()));
-        m_programmaticScrollAnimatorTimeline.clear();
-    }
-
     m_page = nullptr;
     for (const auto& scrollbar : m_horizontalScrollbars)
         GraphicsLayer::unregisterContentsLayer(scrollbar.value->layer());