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

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https://hg.mozilla.org/integration/gaia-central/rev/2bdd709193b7
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Merge pull request #13544 from pivanov/bug-936009

Bug 936009 - [Email] Update send email screen r=asuth

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https://hg.mozilla.org/integration/gaia-central/rev/3351c5840ff9
Author: Pavel Ivanov <pivanov@mozilla.com>
Desc: Bug 936009 - [Email] Update send email screen