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

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https://hg.mozilla.org/integration/gaia-central/rev/bcfd9bdf5bc5
Author: Mason Chang <mason@masonchang.com>
Desc: Merge pull request #16127 from changm/bug968478

Bug 968478. Put scrollable opaque layer in calendar app. r=21

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https://hg.mozilla.org/integration/gaia-central/rev/2fed5cf4cd0b
Author: Mason Chang <mchang@mozilla.com>
Desc: Bug 968478. Put scrollable opaque layer in calendar app
Bumping manifests a=b2g-bump