Raise the take-shot-of-a-shot error properly, and catch errors from hotkey
Raise the take-shot-of-a-shot error properly, and catch errors from hotkey

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