Revert of Move logic of recording main thread scrolling reasons from cc to blink::ScrollManager

third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h

Index: third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h
diff --git a/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h b/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h
index 8a3e916091b40dc774ef1e0bfbfb2dbde21e8ea6..0a348662a9baa98a5ee1c03ae0a0724f0af5ea04 100644
--- a/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h
+++ b/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h
@@ -479,12 +479,14 @@
   StickyConstraintsMap& GetStickyConstraintsMap() {
     return EnsureRareData().sticky_constraints_map_;
   }
-
   void InvalidateAllStickyConstraints();
   void InvalidateStickyConstraintsFor(PaintLayer*,
                                       bool needs_compositing_update = true);
-  uint32_t GetNonCompositedMainThreadScrollingReasons() {
-    return non_composited_main_thread_scrolling_reasons_;
+
+  void RemoveStyleRelatedMainThreadScrollingReasons();
+  void AddStyleRelatedMainThreadScrollingReasons(const uint32_t);
+  bool HasMainThreadScrollingReason(uint32_t reason) const {
+    return reasons_ & reason;
   }
 
   uint64_t Id() const;
@@ -595,7 +597,7 @@
   std::unique_ptr<PaintLayerScrollableAreaRareData> rare_data_;
 
   // MainThreadScrollingReason due to the properties of the LayoutObject
-  uint32_t non_composited_main_thread_scrolling_reasons_;
+  uint32_t reasons_;
 
 #if DCHECK_IS_ON()
   bool has_been_disposed_;