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

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https://hg.mozilla.org/integration/gaia-central/rev/0f4f24675eee
Author: James Burke <jrburke@gmail.com>
Desc: Merge pull request #15572 from jrburke/bug962149-email-nopersist-edit

Bug 962149 - [E-Mail][UI] HTML cache saves/serializes edit mode state r=asuth

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https://hg.mozilla.org/integration/gaia-central/rev/4229ba072ff2
Author: jrburke <jrburke@gmail.com>
Desc: Bug 962149 - [E-Mail][UI] HTML cache saves/serializes edit mode state
Bumping manifests a=b2g-bump