Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/9ed302828ccb
Author: Rick Waldron <waldron.rick@gmail.com>
Desc: Revert "Bug 964862 - [Messages][Drafts][Refactoring] Move MessageManager.draft to ThreadUI.draft"

This reverts commit df7b1fe4d0d93d5e3b9621fface6b091eb7ea84e.
Bumping manifests a=b2g-bump