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

========

https://hg.mozilla.org/integration/gaia-2_0/rev/d11e67efb515
Author: Ghislain 'Aus' Lacroix <aus@noiseport.org>
Desc: Merge pull request #20782 from nullaus/v2.0

Merge pull request #20674 from nullaus/bug1021857

========

https://hg.mozilla.org/integration/gaia-2_0/rev/85af188a1535
Author: Ghislain 'Aus' Lacroix <aus@noiseport.org>
Desc: Merge pull request #20674 from nullaus/bug1021857

bug 1021857 - Ensure z-index for AttentionScreen makes it top-most.
(cherry picked from commit f2b7236f28d528cd2a12691fba004e1a2afa929d)
Bumping manifests a=b2g-bump