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

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https://hg.mozilla.org/integration/gaia-central/rev/8539eb2c32f0
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #12426 from GeorgiaWang/Bug919969

Bug 919969 - Add illegal sim state support in Settings

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https://hg.mozilla.org/integration/gaia-central/rev/22406a06f44c
Author: Georgia Wang <gwang@mozilla.com>
Desc: Bug 919969 - Add illegal sim state support in Settings