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

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https://hg.mozilla.org/integration/gaia-central/rev/2cd760a699de
Author: Rudy Lu <me@rudy.lu>
Desc: Merge pull request #21807 from RudyLu/keyboard/Bug1038131-remove_selectionchange_listener

Bug 1038131 - latin.js failed to deactivate and continue to respond to
r=timdream.

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https://hg.mozilla.org/integration/gaia-central/rev/3cb87c1b04da
Author: Rudy Lu <me@rudy.lu>
Desc: Bug 1038131 - latin.js failed to deactivate and continue to respond to
selectionchange.
 - Remove the event listener for 'selectionchange' in IME's deactivate().
Bumping manifests a=b2g-bump