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

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https://hg.mozilla.org/integration/gaia-central/rev/531f9dc340de
Author: Yuren Ju <yurenju@gmail.com>
Desc: Merge pull request #23559 from xfq/Bug1032005r2

Bug 1032005 - Fix jshint error for build/download-manager.js r=yurenju

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https://hg.mozilla.org/integration/gaia-central/rev/244a39c49211
Author: Xue Fuqiao <xfq.free@gmail.com>
Desc: Bug 1032005 - Fix jshint error for build/download-manager.js
Bumping manifests a=b2g-bump