nsITimer can be used off the main thread and we do it in the new network cache. This test registers its own JS implementation of timer which causes a crash in our code. See bug #968101 comment 8.

The test has been disabled by bug #968101.

Michal, I think the solution is to use CID to get the timer in our code and not the ContractID.

this xpcshell test doesn't need the cache (well I suppose most of them don't), couldn't we simply disable the cache for this specific test? does the timer run regardless? Btw, if you want to use the CID to avoid possible issues with add-ons replacing nsITimer, you can do that, though I don't think you should just for this single case. Indeed this test is enough of a hack, I should rather rewrite it to not need to mock nsITimer (the component may fire a notification when the internal timer changes and the test could observe that).

This has been fixed in the meanwhile, the test got rewritten in bug 889561.