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

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https://hg.mozilla.org/integration/gaia-central/rev/e77a67b02714
Author: Corey Frang <gnarf37@gmail.com>
Desc: Bug 917337 - [Clock] Implement Scrolling for Timer Settings

https://bugzilla.mozilla.org/show_bug.cgi?id=917337

- Adds overflow-y: auto to #timer-dialog
- Adds a event.preventDefault() on touchstart on the time picker to stop user from scrolling while spinning inputs

r=jugglinmike