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

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https://hg.mozilla.org/integration/gaia-central/rev/3867549a6589
Author: Jan Jongboom <janjongboom@gmail.com>
Desc: Merge pull request #12853 from vkrreddy2/920407_keyboard

Bug 920407 - keyboard: adding place holder to white space. r=janjongboom

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https://hg.mozilla.org/integration/gaia-central/rev/084988a39fc9
Author: kodanda.v <kodanda.v@borqs.com>
Desc: Bug 920407 - keyboard: adding place holder to white space.