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

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https://hg.mozilla.org/integration/gaia-central/rev/ae6c71b5ee28
Author: Arthur Chen <crh0716@gmail.com>
Desc: Merge pull request #10818 from crh0716/874313_1

Bug 874313 - Modify messages for the case of unavaliable media storage r=dkuo, dale

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https://hg.mozilla.org/integration/gaia-central/rev/4f3a8923c73c
Author: crh0716 <crh0716@gmail.com>
Desc: Bug 874313 - Display a dialog in media apps when the default storage is unavailable.