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

========

https://hg.mozilla.org/integration/gaia-central/rev/cba6294f97cb
Author: Diego Marcos <diego.marcos@gmail.com>
Desc: Merge pull request #16679 from dmarcos/bug977422

Bug 977422 - [Camera] When recording fails the controls have to be re en...

========

https://hg.mozilla.org/integration/gaia-central/rev/78b580a4ee08
Author: Diego Marcos <diego.marcos@gmail.com>
Desc: Bug 977422 - [Camera] When recording fails the controls have to be re enabled
Bumping manifests a=b2g-bump