Calling Text.appendData() / Comment.appendData() without parameter should throw: https://dom.spec.whatwg.org/#characterdata (parameter is mandatory) However, WebKit currently does not throw and appends the string "undefined". Firefox and Chrome match the specification and throw in this case.
rdar://problem/22546954
Created attachment 261078 [details] Patch
Comment on attachment 261078 [details] Patch Clearing flags on attachment: 261078 Committed r189676: <http://trac.webkit.org/changeset/189676>
All reviewed patches have been landed. Closing bug.