setAttribute("border", null) on a table creates a border

At the moment WebKit is the only rendering engine that regards
setAttribute("border", null) as not setting a border on a table. All
other set a border, even in strict mode.

Although the odd one out, WebKit seems to be correct per the DOM4 and
IDL specs. See https://bugs.webkit.org/show_bug.cgi?id=102112

I'd like to make WebKit interoperable on this with other browsers, so
can we get the current treatment of 'null' as setting a border added
to the spec?