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

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https://hg.mozilla.org/integration/gaia-central/rev/8674266eb505
Author: Arthur Chen <crh0716@gmail.com>
Desc: Merge pull request #24925 from crh0716/1007600

Bug 1007600 - Support inline activity r=eragonj, alive

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https://hg.mozilla.org/integration/gaia-central/rev/aa8ab37129b4
Author: Arthur Chen <crh0716@gmail.com>
Desc: Bug 1007600 - Support inline activity
Bumping manifests a=b2g-bump