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

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https://hg.mozilla.org/integration/gaia-central/rev/f2520364a26a
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #20831 from KevinGrandon/bug_1028351_take_2

Bug 1028351 - [Vertical] Vertical App name should be localized

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https://hg.mozilla.org/integration/gaia-central/rev/b3bdc20fe1dc
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1028351 - [Vertical] Vertical App name should be localized r=tchevalier r=lightsofapollo
Bumping manifests a=b2g-bump