Reviewed by darin and mjs.
        
        Add better SVGLoad event support.
        http://bugzilla.opendarwin.org/show_bug.cgi?id=6010
        There will still need to be additional support added for <link> and <script> elements.
        Not all of the error -> loaded -> error transition cases work yet.

        * dom/EventTargetNode.cpp:
        (WebCore::EventTargetNode::dispatchGenericEvent):
        * html/HTMLImageLoader.cpp:
        (WebCore::HTMLImageLoader::dispatchLoadEvent):
        * html/HTMLImageLoader.h:
        (WebCore::HTMLImageLoader::haveFiredLoadEvent):
        (WebCore::HTMLImageLoader::setHaveFiredLoadEvent):
        * ksvg2/misc/SVGImageLoader.cpp:
        (WebCore::SVGImageLoader::SVGImageLoader):
        (WebCore::SVGImageLoader::dispatchLoadEvent):
        * ksvg2/misc/SVGImageLoader.h:
        * ksvg2/svg/SVGAElement.cpp:
        (WebCore::SVGAElement::parseMappedAttribute):
        * ksvg2/svg/SVGAnimatedBoolean.h:
        * ksvg2/svg/SVGElement.cpp:
        (WebCore::SVGElement::SVGElement):
        (WebCore::SVGElement::parseMappedAttribute):
        (WebCore::SVGElement::haveLoadedRequiredResources):
        (WebCore::SVGElement::sendSVGLoadEventIfPossible):
        (WebCore::SVGElement::closeRenderer):
        * ksvg2/svg/SVGElement.h:
        (WebCore::SVGElement::rendererIsNeeded):
        (WebCore::svg_dynamic_cast):
        * ksvg2/svg/SVGExternalResourcesRequired.h:
        * ksvg2/svg/SVGImageElement.cpp:
        (SVGImageElement::SVGImageElement):
        (SVGImageElement::haveLoadedRequiredResources):
        * ksvg2/svg/SVGImageElement.h:
        * ksvg2/svg/SVGSVGElement.cpp:
        (WebCore::SVGSVGElement::parseMappedAttribute):
        * ksvg2/svg/SVGScriptElement.cpp:
        (WebCore::SVGScriptElement::SVGScriptElement):
        (WebCore::SVGScriptElement::parseMappedAttribute):
        (WebCore::SVGScriptElement::executeScript):
        * xml/xmlhttprequest.cpp:
        (WebCore::XMLHttpRequest::callReadyStateChangeListener): use new Event() instead of createEvent


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@15870 268f45cc-cd09-0410-ab3c-d52691b4dbfc