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

========

https://hg.mozilla.org/integration/gaia-central/rev/a35b39306d94
Author: gasolin <gasolin@gmail.com>
Desc: Merge pull request #17850 from gasolin/issue-990561

Bug 990561 - [MADAI][System] @2.25x assets update for Emergency Call, r=greg

========

https://hg.mozilla.org/integration/gaia-central/rev/707a0beaeba1
Author: gasolin <gasolin@gmail.com>
Desc: Bug 990561 - [MADAI][System] @2.25x assets update for Emergency Call
Bumping manifests a=b2g-bump