Fix #1377, bad pages won't keep onDestroy from being called, and so it will better track when PageShot is open
Fix #1377, bad pages won't keep onDestroy from being called, and so it will better track when PageShot is open

fzzzy/pageshot,mozilla-services/screenshots,fzzzy/pageshot,mozilla-services/screenshots,mozilla-services/screenshots,mozilla-services/pageshot,fzzzy/pageshot,mozilla-services/pageshot,mozilla-services/screenshots,mozilla-services/pageshot,fzzzy/pageshot,mozilla-services/pageshot