Bumping gaia.json for 2 gaia-1_2 revision(s) a=gaia-bump

========

https://hg.mozilla.org/integration/gaia-1_2/rev/59d30d2a6556
Author: gitmai <mri@tid.es>
Desc: Merge pull request #14390 from gitmai/bug-944718-Broken-usage-widget_v1.2

Bug 944718 - [Cost Control] Broken access to usage widget from utility t...
r=jmcf

========

https://hg.mozilla.org/integration/gaia-1_2/rev/39091e360d48
Author: mai <mri@tid.es>
Desc: Bug 944718 - [Cost Control] Broken access to usage widget from utility tray