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

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https://hg.mozilla.org/integration/gaia-central/rev/a822c2d25b93
Author: George <georgeiscoming@gmail.com>
Desc: Merge pull request #13603 from cctuan/937039

Bug 937039 - [Flatfish] raise zindex of home gesture panel(fix regression of bug 919492

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https://hg.mozilla.org/integration/gaia-central/rev/d24a49e14f8a
Author: cctuan <georgeiscoming@gmail.com>
Desc: Bug 937039 - [Flatfish] raise zindex of home gesture panel(fix regression of bug 919492