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

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https://hg.mozilla.org/integration/gaia-central/rev/c6fe37f9bcd9
Author: George <georgeiscoming@gmail.com>
Desc: Merge pull request #13436 from cctuan/935352

Bug 935352 - [Flatfish] Dock panel is fixed still until 7th~8th app icons landed

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https://hg.mozilla.org/integration/gaia-central/rev/c9611593fe55
Author: cctuan <georgeiscoming@gmail.com>
Desc: Bug 935352 - [Flatfish] Dock panel is fixed still until 7th~8th app icons landed