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

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https://hg.mozilla.org/integration/gaia-central/rev/fb858cbb461d
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Merge pull request #13700 from Pike/bug-938052-keyboard-js-errors

bug 938052, better report js errors in keyboard layouts, and fix a few, r=djf, rudyl, yuren

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https://hg.mozilla.org/integration/gaia-central/rev/9c9595a3d0de
Author: Axel Hecht <axel@pike.org>
Desc: bug 938052, better report js errors in keyboard layouts, and fix a few