Bug 738818 followup: remove now-unused portions of test
Bug 860033 - un-generic-ify _showExceptions, r=gavin

--HG--
extra : rebase_source : 0a1dd71567a95892e0a8ad40c513c8baeb63be57
Bug 848935 - Skip spurious load events for intermittent failures in browser_aboutHome.js