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

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https://hg.mozilla.org/integration/gaia-central/rev/553d71d2b228
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #17082 from KevinGrandon/bug_982084_contacts_marionette_jshint

Bug 982084 - [Contacts] JSHint fixes for test/marionette/ r=arcturus

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https://hg.mozilla.org/integration/gaia-central/rev/ff4a76c2663a
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 982084 - [Contacts] JSHint fixes for test/marionette/ r=arcturus
Bumping manifests a=b2g-bump