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

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https://hg.mozilla.org/integration/gaia-central/rev/7b8064a8f699
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #11121 from alivedise/bugzilla/896773/do-callback

Bug 896773 - Do invoke callback anytime in window manager, r=timdream, a=leo+

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https://hg.mozilla.org/integration/gaia-central/rev/2d1eb15216bd
Author: Alive Kuo <alegnadise@gmail.com>
Desc: Bug 896773 - Do invoke callback anytime in window manager