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

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https://hg.mozilla.org/integration/gaia-central/rev/67b48b77c214
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #22854 from dholbert/1050431-remove-lines

Bug 1050431: Remove unnecessary 'flex' decls from video.css (equivalent to default values). r=djf

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https://hg.mozilla.org/integration/gaia-central/rev/de8e87e3fe75
Author: Daniel Holbert <dholbert@cs.stanford.edu>
Desc: Bug 1050431: Remove unnecessary 'flex' decls from video.css (equivalent to default values). r=djf
Bumping manifests a=b2g-bump