Implement getIntersectionList(), getEnclosureList(), checkIntersection() and checkEnclosure() in SVGSVGElement
        https://bugs.webkit.org/show_bug.cgi?id=11274

        Reviewed by Nikolas Zimmermann.

        Implement checkIntersection/checkEnclosure and use it to implement getIntersectionList and getEnclosureList as well.
        The referenceElement is used to provide a DOM subtree to find matches in. Also we do not allow elements that specify
        pointer-events=none in the list.

        Tests: svg/W3C-SVG-1.1-SE/struct-dom-11-f.svg
               svg/custom/intersection-list-clipping.svg
               svg/custom/intersection-list-nested-svg.svg

        * rendering/svg/RenderSVGModelObject.cpp:
        (WebCore::getElementCTM):
        (WebCore::intersectsAllowingEmpty):
        (WebCore::isGraphicsElement):
        (WebCore::RenderSVGModelObject::checkIntersection):
        (WebCore::RenderSVGModelObject::checkEnclosure):
        * rendering/svg/RenderSVGModelObject.h:
        * svg/SVGSVGElement.cpp:
        (WebCore::SVGSVGElement::checkIntersection):
        (WebCore::SVGSVGElement::checkEnclosure):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@91850 268f45cc-cd09-0410-ab3c-d52691b4dbfc