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

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https://hg.mozilla.org/integration/gaia-central/rev/a424a1880e5f
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #13187 from borjasalguero/uk_v1.2_sprint4_forwad_logic

Bug 927784 - [Messaging][Forward] Implement forward logic. r=rwaldron,julienw

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https://hg.mozilla.org/integration/gaia-central/rev/e85214653f6d
Author: borjasalguero <fbsc@tid.es>
Desc: Bug 927784 - [Messaging][Forward] Implement forward logic. r=rwaldron,julienw