Simple test cases demonstrate that <object> won't show its fallback content if both the URL and the MIME type are omitted.
Created attachment 16999 [details] patch
<rdar://problem/5530185>
Comment on attachment 16999 [details] patch + (-[WebNullPluginView reportFailure]): Added. Does the actual delegate + callback. Happens back at the top level of the run loop so it doesn't + fire deep inside layout. Also wrote this so that it is guaranteed not to + reenter and so that it can handle the case where the delegate destroys + the world (including this object). This is good to fix for WebKit's own Null plugin, (you're fixing bug 15405), but other WebKit plugins can still presumably run arbitrary code under attach(), either mutating the DOM or putting up a sheet, which will cause reentry into WebCore.
Comment on attachment 16999 [details] patch r=me. I just need to make sure to follow up on bug 15404 if it gets closed as a result (which it should).
(In reply to comment #4) > bug 15404 I mean bug 15405.
Committed revision 27378.
*** Bug 7536 has been marked as a duplicate of this bug. ***
*** Bug 15202 has been marked as a duplicate of this bug. ***