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

========

https://hg.mozilla.org/integration/gaia-central/rev/701fe69c5ccf
Author: Jan Keromnes <janx@linux.com>
Desc: Merge pull request #18940 from jankeromnes/homescreen

Bug 1005880 - [Homescreen] Don't calculate velocity more than once for a timestamp. r=djf

========

https://hg.mozilla.org/integration/gaia-central/rev/6a3491e5870b
Author: Jan Keromnes <janx@linux.com>
Desc: Bug 1005880 - [Homescreen] Don't calculate velocity more than once for a timestamp. r=djf
Bumping manifests a=b2g-bump