Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/2f64eeaddcd8
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Bug 984718 - [keyboard refactor] Add test/unit/.jshintrc
Bumping manifests a=b2g-bump