Bug 1020766 - fix [Flatfish][Gallery]Gallery app shows last-deleted photo in  the preview window

https://bugzilla.mozilla.org/show_bug.cgi?id=1020766
There's lint error which is causing travis lint job to fail. Please fix

https://travis-ci.org/mozilla-b2g/gaia/jobs/28970848
----- FILE  :  /home/travis/build/mozilla-b2g/gaia/apps/gallery/js/gallery.js -----
Line 666, E:0110: Line too long (81 characters).

Checked and Unit test travis failure are not related to this patch.