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

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https://hg.mozilla.org/integration/gaia-central/rev/376d2a4ce65d
Author: Fabien Cazenave <fabien@mozilla.com>
Desc: Merge pull request #16743 from fabi1cazenave/customDataIcons-bug976951

Bug 976951: custom data icons for the quick settings, r=vingtetun

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https://hg.mozilla.org/integration/gaia-central/rev/46ad90c32e9e
Author: Carmen Jimenez Cabezas <cjc@tid.es>
Desc: Bug 976951 - Customize network indicator displayed in quick settings
r=vingtetun
Bumping manifests a=b2g-bump