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

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https://hg.mozilla.org/integration/gaia-central/rev/e3eadf39c12a
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #12742 from dwi2/bug921930

Bug 921930 - Implement asyncSemaphore for sound manager settings R/W, r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/dadfda8a9484
Author: tzhuang <tzhuang@mozilla.com>
Desc: Bug 921930 - [B2G][Helix][Setting][Sound][Bug][shijinde]The vibrate state is error by Setting the volume mute and unmute in sleep menu function