Bumping gaia.json for 3 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/da603fbb81a7
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Revert "Bug 1055299: Ignore continuous app launch request in homescreen side and send homescreen to background while rocketbar is open in system side"

This reverts commit 20b9139dfe494fa98f73d20aa4e42c13897fbddd.

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https://hg.mozilla.org/integration/gaia-central/rev/3aa7a6f6890d
Author: Zibi Braniecki <zbigniew.braniecki@gmail.com>
Desc: Merge pull request #24152 from zbraniecki/1052136-clean-up-mozl10n-api-in-communications-common

Bug 1052136 - Clean up mozL10n API use in Communications, part 1, shared components. r=jmcf, fcampo

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https://hg.mozilla.org/integration/gaia-central/rev/81c083826d4d
Author: Zbigniew Braniecki <gandalf@mozilla.com>
Desc: Bug 1052136 - Clean up mozL10n API use in Communications, part 1, shared components
Bumping manifests a=b2g-bump