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

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https://hg.mozilla.org/integration/gaia-central/rev/46f6c95fd30b
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #18373 from viorelaioia/bug_997185

Bug 997185 - xfail test_everythingme_add_collection because Bug 995949 -...

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https://hg.mozilla.org/integration/gaia-central/rev/f01d50518e04
Author: Viorela Ioia <viorelaioia@gmail.com>
Desc: Bug 997185 - xfail test_everythingme_add_collection because Bug 995949 - Cannot add smart collection to homescreen
Bumping manifests a=b2g-bump