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

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https://hg.mozilla.org/integration/gaia-central/rev/5ba8325e95de
Author: Arthur Chen <crh0716@gmail.com>
Desc: Merge pull request #12850 from crh0716/920722

Bug 920722 - Change the layout to avoid overlapping r=evelyn

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https://hg.mozilla.org/integration/gaia-central/rev/9d9b2ecca8a8
Author: Arthur Chen <crh0716@gmail.com>
Desc: Bug 920722 - Change the layout to avoid overlapping