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

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https://hg.mozilla.org/integration/gaia-central/rev/25226d7b6f80
Author: Dominic Kuo <dkuo@mozilla.com>
Desc: Merge pull request #14550 from dominickuo/bug-945464

Bug 945464 - [music] add will-animate to music app, r=dominickuo

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https://hg.mozilla.org/integration/gaia-central/rev/2878510b81af
Author: Mason Chang <mchang@mozilla.com>
Desc: Bug 945464 - [music] add will-animate to music app