Removed main-thread one dimensional scrolling paths.

third_party/WebKit/Source/core/layout/LayoutBox.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2006, 2007 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 673 matching lines @@
     // There are a few cases where we need to refer specifically to the available physical width and available physical height.
     // Relative positioning is one of those cases, since left/top offsets are physical.
     LayoutUnit availableWidth() const { return style()->isHorizontalWritingMode() ? availableLogicalWidth() : availableLogicalHeight(IncludeMarginBorderPadding); }
     LayoutUnit availableHeight() const { return style()->isHorizontalWritingMode() ? availableLogicalHeight(IncludeMarginBorderPadding) : availableLogicalWidth(); }
 
     int verticalScrollbarWidth() const;
     int horizontalScrollbarHeight() const;
     int intrinsicScrollbarLogicalWidth() const;
     int scrollbarLogicalWidth() const { return style()->isHorizontalWritingMode() ? verticalScrollbarWidth() : horizontalScrollbarHeight(); }
     int scrollbarLogicalHeight() const { return style()->isHorizontalWritingMode() ? horizontalScrollbarHeight() : verticalScrollbarWidth(); }
-    virtual ScrollResultOneDimensional scroll(ScrollDirectionPhysical, ScrollGranularity, float delta = 1);
+    virtual ScrollResult scroll(ScrollGranularity, const FloatSize&);
     bool canBeScrolledAndHasScrollableArea() const;
     virtual bool canBeProgramaticallyScrolled() const;
     virtual void autoscroll(const IntPoint&);
     bool canAutoscroll() const;
     IntSize calculateAutoscrollDirection(const IntPoint& pointInRootFrame) const;
     static LayoutBox* findAutoscrollable(LayoutObject*);
     virtual void stopAutoscroll() { }
     virtual void panScroll(const IntPoint&);
 
     bool hasAutoVerticalScrollbar() const { return hasOverflowClip() && (style()->overflowY() == OAUTO || style()->overflowY() == OPAGEDY || style()->overflowY() == OOVERLAY); }
@@ skipping 426 matching lines @@
         if (UNLIKELY(m_inlineBoxWrapper != nullptr))
             deleteLineBoxWrapper();
     }
 
     m_inlineBoxWrapper = boxWrapper;
 }
 
 } // namespace blink
 
 #endif // LayoutBox_h