Bumping gaia.json for 3 gaia revision(s) a=gaia-bump

========

https://hg.mozilla.org/integration/gaia-central/rev/92b742f333b1
Author: vingtetun <21@vingtetun.org>
Desc: Merge pull request #22422 from vingtetun/theme-color-landing

Bug 1047311 - Change the set of colors based on the brightness of the theme-color. r=kgrandon

========

https://hg.mozilla.org/integration/gaia-central/rev/34f31878c369
Author: Vivien Nicolas <vnicolas@mozilla.com>
Desc: Bug 1047311 - Change the set of colors based on the brightness of the theme-color. System part. r=kgrandon

========

https://hg.mozilla.org/integration/gaia-central/rev/2c301f182847
Author: Vivien Nicolas <vnicolas@mozilla.com>
Desc: Bug 1047311 - Change the set of colors based on the brightness of the theme-color. r=kgrandon
Bumping manifests a=b2g-bump