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

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https://hg.mozilla.org/integration/gaia-central/rev/5289f109a184
Author: Gregor Wagner <anygregor@gmail.com>
Desc: Merge pull request #13154 from gregorwagner/settings3

Bug 921721 - Use settingsLock.closed. r=timdream

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https://hg.mozilla.org/integration/gaia-central/rev/618c9a3727de
Author: Gregor Wagner <anygregor@gmail.com>
Desc: Bug 921721 - Use settingsLock.closed