Add support for a new property for custom highlighting. This patch just

    Add support for a new property for custom highlighting.  This patch just
        adds support for the parsing of the property.  It doesn't do anything yet.

        Reviewed by beth

        * css/CSSComputedStyleDeclaration.cpp:
        (WebCore::):
        (WebCore::CSSComputedStyleDeclaration::getPropertyCSSValue):
        * css/CSSPropertyNames.in:
        * css/cssparser.cpp:
        (WebCore::CSSParser::parseValue):
        * css/cssstyleselector.cpp:
        (WebCore::CSSStyleSelector::applyProperty):
        * rendering/render_style.cpp:
        (WebCore::StyleCSS3InheritedData::StyleCSS3InheritedData):
        (WebCore::StyleCSS3InheritedData::operator==):
        (WebCore::RenderStyle::diff):
        * rendering/render_style.h:
        (WebCore::RenderStyle::highlight):
        (WebCore::RenderStyle::setHighlight):
        (WebCore::RenderStyle::initialHighlight):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@14763 268f45cc-cd09-0410-ab3c-d52691b4dbfc