Bumping gaia.json for 3 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/8227bc1f33b0
Author: Ben Kelly <ben@wanderview.com>
Desc: Revert "Merge pull request #14589 from rnowm/settings-icons"

This reverts commit 16f95c8500a9f8eb793aa3501871edd292cd7968, reversing
changes made to 4adbbdc32ad62b7fba838d9beeaad3cff7f96651.

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https://hg.mozilla.org/integration/gaia-central/rev/dfb4f3f2f8ac
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Merge pull request #14810 from etiennesegonzac/bug-946316-mochitest

Bug 946316 - Adding data store access to the mochitest app. r=etienne

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https://hg.mozilla.org/integration/gaia-central/rev/f6b03eaa4eda
Author: Andrea Marchesini <amarchesini@mozilla.com>
Desc: Bug 946316 - Adding data store access to the mochitest app. r=etienne