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

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https://hg.mozilla.org/integration/gaia-central/rev/911dd4c19275
Author: James Burke <jrburke@gmail.com>
Desc: Merge pull request #25788 from jrburke/bug1093371-email-refactor-cleanup

Bug 1093371 - [email] Small cleanup from bug 1005446 refactoring r=asuth

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https://hg.mozilla.org/integration/gaia-central/rev/bc2a43d065b1
Author: jrburke <jrburke@gmail.com>
Desc: Bug 1093371 - [email] Small cleanup from bug 1005446 refactoring
Bumping manifests a=b2g-bump