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

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https://hg.mozilla.org/integration/gaia-central/rev/70b8a8a631b1
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #14463 from julienw/946678-use-href-for-activity

Bug 946678 - [Messaging] Creating a new message from contacts does not o...

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https://hg.mozilla.org/integration/gaia-central/rev/64158f1e1f9c
Author: Julien Wajsberg <felash@gmail.com>
Desc: Bug 946678 - [Messaging] Creating a new message from contacts does not open the messaging composer when Messaging app is in background r=borja

Adds a hash for the "new" activity. This will have the side-effect of not
registering the notification and sms-received system message handlers which is a
good thing.