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

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https://hg.mozilla.org/integration/gaia-central/rev/2805066a7ecf
Author: Fabien Cazenave <fabien@mozilla.com>
Desc: Merge pull request #15114 from fabi1cazenave/addIcon-bug956942

Bug 956942 - update shared/style/headers for the `organic' skin, r=pivanov

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https://hg.mozilla.org/integration/gaia-central/rev/cf71373aa589
Author: Fabien Cazenave <fabien@cazenave.cc>
Desc: Bug 956942 - update shared/style/headers for the `organic' skin, r=pivanov
Bumping manifests a=b2g-bump