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

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https://hg.mozilla.org/integration/gaia-central/rev/d2dbb99dd87c
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Merge pull request #13498 from timdream/keyboard-preload

Bug 936349 - Correct keyboard manager start-up, r=rudyl

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https://hg.mozilla.org/integration/gaia-central/rev/72e5af4570b1
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Bug 936349 - Correct keyboard manager start-up