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

third_party/WebKit/Source/core/frame/FrameView.h

 /*
    Copyright (C) 1997 Martin Jones (mjones@kde.org)
              (C) 1998 Waldo Bastian (bastian@kde.org)
              (C) 1998, 1999 Torben Weis (weis@kde.org)
              (C) 1999 Lars Knoll (knoll@kde.org)
              (C) 1999 Antti Koivisto (koivisto@kde.org)
    Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights
    reserved.
 
    This library is free software; you can redistribute it and/or
@@ skipping 778 matching lines @@
   //.B...C.
   //.|.....
   //.D.....
   // If B has fixed background-attachment but other frames
   // don't, both A and C should scroll on cc. Frame D should
   // scrolled on main thread as its ancestor B.
   void updateSubFrameScrollOnMainReason(const Frame&,
                                         MainThreadScrollingReasons);
   String mainThreadScrollingReasonsAsText() const;
   // Main thread scrolling reasons including reasons from ancestors.
   MainThreadScrollingReasons mainThreadScrollingReasons() const;

[bokan, 2017/04/07 17:39:03]

We should probably DCHECK in this and the below method they don't have any
non-composited reasons.

[yigu, 2017/04/07 19:26:27]

Done.

   // Main thread scrolling reasons for this object only. For all reasons,
   // see: mainThreadScrollingReasons().
   MainThreadScrollingReasons mainThreadScrollingReasonsPerFrame() const;
-  void adjustStyleRelatedMainThreadScrollingReasons(const uint32_t reason,
-                                                    bool increase);
-  MainThreadScrollingReasons getStyleRelatedMainThreadScrollingReasons() const;
 
   bool hasVisibleSlowRepaintViewportConstrainedObjects() const;
 
   // Called on a view for a LocalFrame with a RemoteFrame parent. This makes
   // viewport intersection available that accounts for remote ancestor frames
   // and their respective scroll positions, clips, etc.
   void setViewportIntersectionFromParent(const IntRect&);
   IntRect remoteViewportIntersection();
 
   // This method uses localToAncestorQuad to map a rect into an ancestor's
@@ skipping 394 matching lines @@
   };
   std::unique_ptr<Vector<ObjectPaintInvalidation>>
       m_trackedObjectPaintInvalidations;
 
   // For Slimming Paint v2 only.
   std::unique_ptr<PaintController> m_paintController;
   std::unique_ptr<PaintArtifactCompositor> m_paintArtifactCompositor;
 
   bool m_isStoringCompositedLayerDebugInfo;
   MainThreadScrollingReasons m_mainThreadScrollingReasons;
-  // For recording main thread scrolling reasons
-  // due to layout object properties. e.g. opacity, transform.
-  // The size of the vector depends on the number of
-  // main thread scrolling reasons.
-  Vector<int> m_mainThreadScrollingReasonsCounter;
 
   // TODO(kenrb): Remove these when https://crbug.com/680606 is resolved.
   std::unique_ptr<CompositorAnimationTimeline> m_animationTimeline;
   std::unique_ptr<CompositorAnimationHost> m_animationHost;
 
   Member<PrintContext> m_printContext;
 
   FRIEND_TEST_ALL_PREFIXES(WebViewTest, DeviceEmulationResetScrollbars);
 };
 
@@ skipping 28 matching lines @@
                   frameViewBase.isFrameView());
 DEFINE_TYPE_CASTS(FrameView,
                   ScrollableArea,
                   scrollableArea,
                   scrollableArea->isFrameView(),
                   scrollableArea.isFrameView());
 
 }  // namespace blink
 
 #endif  // FrameView_h