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

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https://hg.mozilla.org/integration/gaia-central/rev/371219ecd2a9
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #17543 from zacc/bug_987034

Bug 987034 - Increase timeout for test_video_* python tests r=askeing

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https://hg.mozilla.org/integration/gaia-central/rev/6ebf3a598136
Author: Zac <zcampbell@mozilla.com>
Desc: Bug 987034 - Increase timeout for test_video_* python tests r=askeing
Bumping manifests a=b2g-bump