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

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https://hg.mozilla.org/integration/gaia-central/rev/179d869e88e6
Author: gasolin <gasolin@gmail.com>
Desc: Merge pull request #19364 from gasolin/issue-996515

Bug 996515 - [NFC] Screen shot does not have move back animation when vi..., r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/3d456fcaa1f6
Author: gasolin <gasolin@gmail.com>
Desc: Bug 996515 - [NFC] Screen shot does not have move back animation when video is failed to share

add test and fix lint
Bumping manifests a=b2g-bump