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

========

https://hg.mozilla.org/integration/gaia-central/rev/515e1675fc2e
Author: Yura Zenevich <yura.zenevich@gmail.com>
Desc: Merge pull request #26267 from yzen/bug-1101192

Bug 1101192 - added labels for missing elements in Email's manual setup.

========

https://hg.mozilla.org/integration/gaia-central/rev/1e04596590aa
Author: Yura Zenevich <yzenevich@mozilla.com>
Desc: Bug 1101192 - added labels for missing elements in Email's manual setup. r=jrburke
Bumping manifests a=b2g-bump