Bumping gaia.json for 1 gaia-central revision(s)

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https://hg.mozilla.org/integration/gaia-central/rev/7e8284bea36c
Author: Rick Waldron <waldron.rick@gmail.com>
Desc: Bug 899003 - [Buri][Buri][SMS] Long press on number in message: menu includes "Call" option r=gnarf

https://bugzilla.mozilla.org/show_bug.cgi?id=899003
Signed-off-by: Rick Waldron <waldron.rick@gmail.com>