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

========

https://hg.mozilla.org/integration/gaia-central/rev/fbeb35ab7f1d
Author: Yuren Ju <yurenju@gmail.com>
Desc: Merge pull request #16814 from waynux/issue970138

Bug 970138 - [Tooling] Add a commit hook to unify the file permision r=@yurenju

========

https://hg.mozilla.org/integration/gaia-central/rev/c08d51bcf664
Author: Tzu-Wen Lin <wayne2833@gmail.com>
Desc: Bug 970138 - [Tooling] Add a commit hook to unify the file permision
Bumping manifests a=b2g-bump