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

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https://hg.mozilla.org/integration/gaia-central/rev/8863a878a014
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Merge pull request #16301 from wilsonpage/bug/972701

[Camera] Stop Icon overlaps with Camera Shutter icon while recording video r=dmarcos a=stability

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https://hg.mozilla.org/integration/gaia-central/rev/87ab9841eeff
Author: Wilson Page <wilsonpage@me.com>
Desc: Bug 972701 - [Camera] Stop Icon overlaps with Camera Shutter icon while recording video

Conflicts:
	apps/camera/style/controls.css
Bumping manifests a=b2g-bump