Remove CSS regions support, keeping a bare minimum to support "region-based" multicol.

Source/core/rendering/RenderTableSection.cpp

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1590 matching lines @@
 bool RenderTableSection::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction action)
 {
     // If we have no children then we have nothing to do.
     if (!firstChild())
         return false;
 
     // Table sections cannot ever be hit tested.  Effectively they do not exist.
     // Just forward to our children always.
     LayoutPoint adjustedLocation = accumulatedOffset + location();
 
-    if (hasOverflowClip() && !locationInContainer.intersects(overflowClipRect(adjustedLocation, locationInContainer.region())))
+    if (hasOverflowClip() && !locationInContainer.intersects(overflowClipRect(adjustedLocation)))
         return false;
 
     if (hasOverflowingCell()) {
         for (RenderObject* child = lastChild(); child; child = child->previousSibling()) {
             // FIXME: We have to skip over inline flows, since they can show up inside table rows
             // at the moment (a demoted inline <form> for example). If we ever implement a
             // table-specific hit-test method (which we should do for performance reasons anyway),
             // then we can remove this check.
             if (child->isBox() && !toRenderBox(child)->hasSelfPaintingLayer()) {
                 LayoutPoint childPoint = flipForWritingModeForChild(toRenderBox(child), adjustedLocation);
@@ skipping 88 matching lines @@
     else
         cellLocation.setX(table()->columnPositions()[effectiveColumn] + horizontalBorderSpacing);
 
     cell->setLogicalLocation(cellLocation);
 
     if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled())
         view()->addLayoutDelta(oldCellLocation - cell->location());
 }
 
 } // namespace WebCore