Clip PaintLayerScrollableArea::scrollIntoView return to layer bounds

third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.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 349 matching lines @@
 
     void positionOverflowControls();
 
     // isPointInResizeControl() is used for testing if a pointer/touch position is in the resize control
     // area.
     bool isPointInResizeControl(const IntPoint& absolutePoint, ResizerHitTestType) const;
     bool hitTestOverflowControls(HitTestResult&, const IntPoint& localPoint);
 
     bool hitTestResizerInFragments(const PaintLayerFragments&, const HitTestLocation&) const;
 
+    // Returns the new position, after scrolling, of the given rect in absolute
+    // coordinates, clipped by the parent's client rect.
     LayoutRect scrollIntoView(const LayoutRect&, const ScrollAlignment& alignX, const ScrollAlignment& alignY, ScrollType = ProgrammaticScroll) override;
 
     // Returns true if scrollable area is in the FrameView's collection of scrollable areas. This can
     // only happen if we're scrollable, visible to hit test, and do in fact overflow. This means that
     // 'overflow: hidden' or 'pointer-events: none' layers never get added to the FrameView's collection.
     bool scrollsOverflow() const { return m_scrollsOverflow; }
 
     // Rectangle encompassing the scroll corner and resizer rect.
     IntRect scrollCornerAndResizerRect() const final;
 
@@ skipping 163 matching lines @@
 #endif
 };
 
 DEFINE_TYPE_CASTS(PaintLayerScrollableArea, ScrollableArea, scrollableArea,
     scrollableArea->isPaintLayerScrollableArea(),
     scrollableArea.isPaintLayerScrollableArea());
 
 } // namespace blink
 
 #endif // LayerScrollableArea_h