Bumping gaia.json for 2 gaia revision(s) a=gaia-bump

========

https://hg.mozilla.org/integration/gaia-central/rev/0931f8c4207c
Author: Greg Weng <snowmantw@gmail.com>
Desc: Merge pull request #22015 from snowmantw/issue1041942

Bug 1041942 - [System] Move Clock from statusbar.js to clock.js

========

https://hg.mozilla.org/integration/gaia-central/rev/785cb293434b
Author: Greg Weng <snowmantw@gmail.com>
Desc: Bug 1041942 - [System] Move Clock from statusbar.js to clock.js
Bumping manifests a=b2g-bump