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

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https://hg.mozilla.org/integration/gaia-central/rev/5d3e5b4601fc
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #12503 from alivedise/bugzilla/920890_master_v2/getscreenshot-delay

Bug 920890 - getScreenshot delays setVisible, r=vivien

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https://hg.mozilla.org/integration/gaia-central/rev/8b089a8e738a
Author: Alive Kuo <alegnadise@gmail.com>
Desc: Bug 920890 - getScreenshot delays setVisible