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

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https://hg.mozilla.org/integration/gaia-central/rev/ec5b3237d577
Author: Zibi Braniecki <zbigniew.braniecki@gmail.com>
Desc: Merge pull request #19835 from zbraniecki/1013929-languagechange

Bug 1013929 - Use the languagechange event instead of a mozSettings observer. r=stas

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https://hg.mozilla.org/integration/gaia-central/rev/35efb6857dab
Author: Zbigniew Braniecki <gandalf@mozilla.com>
Desc: Bug 1013929 - Use the languagechange event instead of a mozSettings observer. r=stas
Bumping manifests a=b2g-bump