we need this to log errors to the console in bug 514033. It would be nice to hold onto a concrete imgRequest pointer, but unfortunately we use a weak reference to prevent cycles, and you can't get a concrete class out of a weak reference.
Created attachment 471999 [details] [diff] [review] patch v1 Added a patch. Flagging joe for review.
Created attachment 474434 [details] [diff] [review] patch v2 Rebased. Carrying over review.
Pushed to mozilla-central: http://hg.mozilla.org/mozilla-central/rev/dbdd01fabe45 Resolving fixed.