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

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https://hg.mozilla.org/integration/gaia-central/rev/87fa9c9b376b
Author: Florin Strugariu <bebef_1987@yahoo.com>
Desc: Merge pull request #19892 from yzen/bug-1018214

Bug 1018214 - adding a number of gaia ui tests for status bar and utilit...

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https://hg.mozilla.org/integration/gaia-central/rev/506220dedd86
Author: Yura Zenevich <yzenevich@mozilla.com>
Desc: Bug 1018214 - adding a number of gaia ui tests for status bar and utility tray accessibility. r=Bebe
Bumping manifests a=b2g-bump