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

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https://hg.mozilla.org/integration/gaia-central/rev/c61d272d29ae
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #10871 from KevinGrandon/bug_882346_add_date_time_mappings_for_now

Bug 882346 - Add date time mappings for now r=vingtetun,lightsofapollo

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https://hg.mozilla.org/integration/gaia-central/rev/8515ff8e847a
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 882346 - Add dom.experimental_forms pref