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

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https://hg.mozilla.org/integration/gaia-central/rev/acd53f668718
Author: Vivien Nicolas <21@vingtetun.org>
Desc: Bug 902465 - Too many CanvasLayer on e.me results hurts panning. part 2. r=ran

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https://hg.mozilla.org/integration/gaia-central/rev/f94712ea7073
Author: Evyatar Amitay <evyatron@gmail.com>
Desc: Bug 902465 - Too many CanvasLayer on e.me results hurts panning. part 1. r=vingtetun