Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/f979dcd48983
Author: BavarianTomcat <tomcat@mozilla.com>
Desc: Revert "Bug 1071707 - Remove browser dependency from marionette tests r=Cwiiis" for git test failures

This reverts commit 14b34f6a05672ad1137981f9b7b1f31e73039bd8.
Bumping manifests a=b2g-bump