Explicitly enforce values size in feColorMatrix.

R=senorblanco@chromium.org
BUG=468519

Review URL: https://codereview.chromium.org/1075413002

git-svn-id: svn://svn.chromium.org/blink/trunk@193571 bbb929c8-8fbe-4397-9dbb-9b2b20218538
bool SVGFEColorMatrixElement::isSupportedAttribute(const QualifiedName& attrName)
{
    DEFINE_STATIC_LOCAL(HashSet<QualifiedName>, supportedAttributes, ());
    if (supportedAttributes.isEmpty()) {
        supportedAttributes.add(SVGNames::typeAttr);
        supportedAttributes.add(SVGNames::valuesAttr);
        supportedAttributes.add(SVGNames::inAttr);
    }
    return supportedAttributes.contains<SVGAttributeHashTranslator>(attrName);
}

bool SVGFEColorMatrixElement::isSupportedAttribute(const QualifiedName& attrName)
{
    DEFINE_STATIC_LOCAL(HashSet<QualifiedName>, supportedAttributes, ());
    if (supportedAttributes.isEmpty()) {
        supportedAttributes.add(SVGNames::typeAttr);
        supportedAttributes.add(SVGNames::valuesAttr);
        supportedAttributes.add(SVGNames::inAttr);
    }
    return supportedAttributes.contains<SVGAttributeHashTranslator>(attrName);
}
