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

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https://hg.mozilla.org/integration/gaia-central/rev/17d3c31fb436
Author: Dominic Kuo <dkuo@mozilla.com>
Desc: Merge pull request #13285 from dominickuo/bug-933110

Bug 933110 - [music2] Fix the jslint errors, r=@es92

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https://hg.mozilla.org/integration/gaia-central/rev/8f3fefd4ed25
Author: Dominic Kuo <dkuo@mozilla.com>
Desc: [music2] Fix the lint errors