Get rid of clampScrollOffset and make maximumScrollPosition sane.

Source/core/paint/DeprecatedPaintLayerScrollableArea.h

 /*
  * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 114 matching lines @@
     ScrollBehavior scrollBehaviorStyle() const override;
 
     double scrollXOffset() const { return m_scrollOffset.width() + scrollOrigin().x(); }
     double scrollYOffset() const { return m_scrollOffset.height() + scrollOrigin().y(); }
 
     DoubleSize scrollOffset() const { return m_scrollOffset; }
 
     // FIXME: We shouldn't allow access to m_overflowRect outside this class.
     LayoutRect overflowRect() const { return m_overflowRect; }
 
-    void scrollToOffset(const DoubleSize& scrollOffset, ScrollOffsetClamping = ScrollOffsetUnclamped, ScrollBehavior = ScrollBehaviorInstant);
+    void scrollToPosition(const DoublePoint& scrollPosition, ScrollOffsetClamping = ScrollOffsetUnclamped, ScrollBehavior = ScrollBehaviorInstant);
+
+    void scrollToOffset(const DoubleSize& scrollOffset, ScrollOffsetClamping clamp = ScrollOffsetUnclamped, ScrollBehavior scrollBehavior = ScrollBehaviorInstant)
+    {
+        scrollToPosition(-scrollOrigin() + scrollOffset, clamp, scrollBehavior);
+    }
 
     void scrollToXOffset(double x, ScrollOffsetClamping clamp = ScrollOffsetUnclamped, ScrollBehavior scrollBehavior = ScrollBehaviorInstant)
     {
         scrollToOffset(DoubleSize(x, scrollYOffset()), clamp, scrollBehavior);
     }
 
     void scrollToYOffset(double y, ScrollOffsetClamping clamp = ScrollOffsetUnclamped, ScrollBehavior scrollBehavior = ScrollBehaviorInstant)
     {
         scrollToOffset(DoubleSize(scrollXOffset(), y), clamp, scrollBehavior);
     }
@@ skipping 90 matching lines @@
     bool hasHorizontalOverflow() const;
     bool hasVerticalOverflow() const;
     bool hasScrollableHorizontalOverflow() const;
     bool hasScrollableVerticalOverflow() const;
     bool visualViewportSuppliesScrollbars() const;
 
     bool needsScrollbarReconstruction() const;
 
     void computeScrollDimensions();
 
-    // TODO(bokan): This method hides the base class version and is subtly different.
-    // Should be unified.
-    DoubleSize clampScrollOffset(const DoubleSize&) const;
-
     void setScrollOffset(const IntPoint&, ScrollType) override;
     void setScrollOffset(const DoublePoint&, ScrollType) override;
 
     LayoutUnit verticalScrollbarStart(int minX, int maxX) const;
     LayoutUnit horizontalScrollbarStart(int minX) const;
     IntSize scrollbarOffset(const Scrollbar*) const;
 
     PassRefPtrWillBeRawPtr<Scrollbar> createScrollbar(ScrollbarOrientation);
     void destroyScrollbar(ScrollbarOrientation);
 
@@ skipping 45 matching lines @@
     LayoutScrollbarPart* m_resizer;
 
 #if ENABLE(ASSERT)
     bool m_hasBeenDisposed;
 #endif
 };
 
 } // namespace blink
 
 #endif // LayerScrollableArea_h