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

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https://hg.mozilla.org/integration/gaia-central/rev/ebb5c473c949
Author: Arthur Chen <crh0716@gmail.com>
Desc: Merge pull request #12487 from crh0716/919884

Bug 919884 - Refresh the displaying connection status based on the real connection status r=evelyn

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https://hg.mozilla.org/integration/gaia-central/rev/9757e9a8cc95
Author: Arthur Chen <crh0716@gmail.com>
Desc: Bug 919884 - Refresh the displaying connection status based on the real connection status