LayoutBox::scrollRectToVisible doesn't respect overflow:hidden property.

third_party/WebKit/Source/platform/scroll/ScrollableArea.cpp

 /*
  * Copyright (c) 2010, Google Inc. All rights reserved.
  * Copyright (C) 2008, 2011 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 195 matching lines @@
     if (scrollBehavior == ScrollBehaviorSmooth)
         programmaticScrollAnimator()->animateToOffset(toFloatPoint(position));
     else
         programmaticScrollAnimator()->scrollToOffsetWithoutAnimation(toFloatPoint(position));
 }
 
 void ScrollableArea::userScrollHelper(const DoublePoint& position, ScrollBehavior scrollBehavior)
 {
     cancelProgrammaticScrollAnimation();
 
+    double x =  userInputScrollable(HorizontalScrollbar) ? position.x() : scrollAnimator()->currentPosition().x();
+    double y =  userInputScrollable(VerticalScrollbar) ? position.y() : scrollAnimator()->currentPosition().y();
+    DoublePoint newPosition(x, y);
+
     // Smooth user scrolls (keyboard, wheel clicks) are handled via the userScroll method.
     // TODO(bokan): The userScroll method should probably be modified to call this method
     //              and ScrollAnimator to have a simpler animateToOffset method like the
     //              ProgrammaticScrollAnimator.
     ASSERT(scrollBehavior == ScrollBehaviorInstant);
-    scrollAnimator()->scrollToOffsetWithoutAnimation(toFloatPoint(position));
+    scrollAnimator()->scrollToOffsetWithoutAnimation(toFloatPoint(newPosition));
 }
 
 void ScrollableArea::scrollIntoRect(const LayoutRect& rectInContent, const FloatRect& targetRectInFrame)
 {
     // Use |pixelSnappedIntRect| for rounding to pixel as opposed to |enclosingIntRect|. It gives a better
     // combined (location and size) rounding error resulting in a more accurate scroll offset.
     // FIXME: It would probably be best to do the whole calculation in LayoutUnits but contentsToRootFrame
     // and friends don't have LayoutRect/Point versions yet.
     IntRect boundsInContent = pixelSnappedIntRect(rectInContent);
     IntRect boundsInFrame(boundsInContent.location() - toIntSize(scrollPosition()), boundsInContent.size());
 
     int centeringOffsetX = (targetRectInFrame.width() - boundsInFrame.width()) / 2;
     int centeringOffsetY = (targetRectInFrame.height() - boundsInFrame.height()) / 2;
 
     IntSize scrollDelta(
         boundsInFrame.x() - centeringOffsetX - targetRectInFrame.x(),
         boundsInFrame.y() - centeringOffsetY - targetRectInFrame.y());
 
     DoublePoint targetOffset = DoublePoint(scrollPosition() + scrollDelta);
 
     setScrollPosition(targetOffset, ProgrammaticScroll);
 }
 
-LayoutRect ScrollableArea::scrollIntoView(const LayoutRect& rectInContent, const ScrollAlignment& alignX, const ScrollAlignment& alignY)
+LayoutRect ScrollableArea::scrollIntoView(const LayoutRect& rectInContent, const ScrollAlignment& alignX, const ScrollAlignment& alignY, ScrollType)
 {
     // TODO(bokan): This should really be implemented here but ScrollAlignment is in Core which is a dependency violation.
     ASSERT_NOT_REACHED();
     return LayoutRect();
 }
 
 void ScrollableArea::scrollPositionChanged(const DoublePoint& position, ScrollType scrollType)
 {
     TRACE_EVENT0("blink", "ScrollableArea::scrollPositionChanged");
 
@@ skipping 344 matching lines @@
         verticalScrollbarWidth = !verticalBar->isOverlayScrollbar() ? verticalBar->width() : 0;
     if (Scrollbar* horizontalBar = horizontalScrollbar())
         horizontalScrollbarHeight = !horizontalBar->isOverlayScrollbar() ? horizontalBar->height() : 0;
 
     return IntSize(std::max(0, size.width() - verticalScrollbarWidth),
         std::max(0, size.height() - horizontalScrollbarHeight));
 
 }
 
 } // namespace blink