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 af3638057b21ad9d63567520d83a252ac2a5eaff..9e77296a4d4f464ac4e8ff6f533f28b2f0bb200a 100644
--- a/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h
+++ b/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h
@@ -481,11 +481,8 @@ class CORE_EXPORT PaintLayerScrollableArea final
   void invalidateStickyConstraintsFor(PaintLayer*,
                                       bool needsCompositingUpdate = true);
 
-  void removeStyleRelatedMainThreadScrollingReasons();
-  void addStyleRelatedMainThreadScrollingReasons(const uint32_t);
-  bool hasMainThreadScrollingReason(uint32_t reason) const {
-    return m_reasons & reason;
-  }
+  void resetStyleRelatedMainThreadScrollingReasons() { m_reasons = 0; }

[bokan, 2017/03/24 17:55:55]

reset only gets called from inside PLSA. Remove this method and just replace
with m_reasons = 0. Also, rename m_reasons to m_mainThreadScrollingReasons

[yigu, 2017/03/27 21:02:08]

Done.

+  uint32_t getStyleRelatedMainThreadScrollingReasons() { return m_reasons; }
 
   uint64_t id() const;