Improve the performance of dynamic sibling and CSS3 selectors so that there is no slowdown any more.
        Be more precise in terms of what nodes we mark dirty.

        Reviewed by Beth

        * css/CSSStyleSelector.cpp:
        (WebCore::CSSStyleSelector::checkSelector):
        * dom/Element.cpp:
        (WebCore::Element::recalcStyle):
        (WebCore::checkForSiblingStyleChanges):
        (WebCore::Element::childrenChanged):
        (WebCore::Element::finishParsingChildren):
        * rendering/RenderStyle.cpp:
        (WebCore::RenderStyle::RenderStyle):
        * rendering/RenderStyle.h:
        (WebCore::RenderStyle::childrenAffectedByPositionalRules):
        (WebCore::RenderStyle::childrenAffectedByDirectAdjacentRules):
        (WebCore::RenderStyle::setChildrenAffectedByDirectAdjacentRules):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@30667 268f45cc-cd09-0410-ab3c-d52691b4dbfc