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

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https://hg.mozilla.org/integration/gaia-central/rev/eb6694cbb975
Author: Bob Silverberg <bob.silverberg@gmail.com>
Desc: Merge pull request #14012 from zacc/bug_937336_messages

Bug 937336 - Python remove explicit frame switching from Messages app ob...

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https://hg.mozilla.org/integration/gaia-central/rev/829f3947e4b7
Author: Zac Campbell <zcampbell@mozilla.com>
Desc: Bug 937336 - Python remove explicit frame switching from Messages app object