All XMLHttpRequest's fail in a pages loaded with WebFrame's loadHTMLString: or loadData:. This failure happens because of the cross-domian check since the frame has a applewebdata://... URL. These URLs should be treated like other file URLs and be allowed to open an XMLHttpRequest to any domain.
Created attachment 11682 [details] Patch XMLHttpRequest fails in a page loaded with WebFrame's loadHTMLString: or loadData: http://bugs.webkit.org/show_bug.cgi?id=11723 Allow cross-domain XMLHTTPRequest for applewebdata URLs. No automated way to test, tested in Safari's debug Snippet Editor. * xml/xmlhttprequest.cpp: (WebCore::XMLHttpRequest::urlMatchesDocumentDomain):
Comment on attachment 11682 [details] Patch r=me
Landed in r17939.