Reviewed by Alice.

        - Tests for http://bugs.webkit.org/show_bug.cgi?id=13541
          REGRESSION: Setting a DOMString attribute to JS null in the 
          JS bindings should default to converting to the empty string

        * fast/dom/document-attribute-js-null-expected.txt: Added.
        * fast/dom/document-attribute-js-null.html: Added.
        * fast/dom/element-attribute-js-null-expected.txt: Added.
        * fast/dom/element-attribute-js-null.html: Added.
        * fast/forms/input-null-expected.txt: Removed.
        * fast/forms/input-null.html: Removed.

WebCore:

        Reviewed by Alice!

        - Patch for http://bugs.webkit.org/show_bug.cgi?id=13541
          REGRESSION: Setting a DOMString attribute to JS null in the 
          JS bindings should default to converting to the empty string

          Convert JS null to the empty string when passing it to an attribute that takes
          a DOMString.

        Test: fast/dom/document-attribute-js-null.html
        Test: fast/dom/element-attribute-js-null.html

        * bindings/js/kjs_dom.cpp:
        (KJS::DOMNode::putValueProperty):
        * bindings/js/kjs_html.cpp:
        (KJS::JSHTMLDocument::putValueProperty):
        (KJS::JSHTMLElement::objectSetter):
        (KJS::JSHTMLElement::embedSetter):
        (KJS::JSHTMLElement::tableSetter):
        (KJS::JSHTMLElement::tableCaptionSetter):
        (KJS::JSHTMLElement::tableColSetter):
        (KJS::JSHTMLElement::tableSectionSetter):
        (KJS::JSHTMLElement::tableRowSetter):
        (KJS::JSHTMLElement::tableCellSetter):
        (KJS::JSHTMLElement::frameSetSetter):
        (KJS::JSHTMLElement::frameSetter):
        (KJS::JSHTMLElement::iFrameSetter):
        (KJS::JSHTMLElement::marqueeSetter):
        (KJS::JSHTMLElement::putValueProperty):
        * bindings/js/kjs_html.h:
        * dom/Document.idl:
        * dom/Node.idl:
        * html/HTMLAnchorElement.idl:
        * html/HTMLAppletElement.idl:
        * html/HTMLAreaElement.idl:
        * html/HTMLBRElement.idl:
        * html/HTMLBaseElement.idl:
        * html/HTMLBaseFontElement.idl:
        * html/HTMLBlockquoteElement.idl:
        * html/HTMLBodyElement.idl:
        * html/HTMLButtonElement.idl:
        * html/HTMLDivElement.idl:
        * html/HTMLDocument.idl:
        * html/HTMLElement.idl:
        * html/HTMLEmbedElement.idl:
        * html/HTMLFontElement.idl:
        * html/HTMLFormElement.idl:
        * html/HTMLFrameElement.idl:
        * html/HTMLFrameSetElement.idl:
        * html/HTMLHRElement.idl:
        * html/HTMLHeadElement.idl:
        * html/HTMLHeadingElement.idl:
        * html/HTMLHtmlElement.idl:
        * html/HTMLIFrameElement.idl:
        * html/HTMLImageElement.idl:
        * html/HTMLInputElement.idl:
        * html/HTMLIsIndexElement.idl:
        * html/HTMLLIElement.idl:
        * html/HTMLLabelElement.idl:
        * html/HTMLLegendElement.idl:
        * html/HTMLLinkElement.idl:
        * html/HTMLMapElement.idl:
        * html/HTMLMetaElement.idl:
        * html/HTMLModElement.idl:
        * html/HTMLOListElement.idl:
        * html/HTMLObjectElement.idl:
        * html/HTMLOptGroupElement.idl:
        * html/HTMLOptionElement.idl:
        * html/HTMLParagraphElement.idl:
        * html/HTMLParamElement.idl:
        * html/HTMLQuoteElement.idl:
        * html/HTMLScriptElement.idl:
        * html/HTMLSelectElement.idl:
        * html/HTMLStyleElement.idl:
        * html/HTMLTableCaptionElement.idl:
        * html/HTMLTableCellElement.idl:
        * html/HTMLTableColElement.idl:
        * html/HTMLTableElement.idl:
        * html/HTMLTableRowElement.idl:
        * html/HTMLTableSectionElement.idl:
        * html/HTMLTextAreaElement.idl:
        * html/HTMLTitleElement.idl:
        * html/HTMLUListElement.idl:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@21470 268f45cc-cd09-0410-ab3c-d52691b4dbfc