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

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https://hg.mozilla.org/integration/gaia-central/rev/43f1f9d6f8b4
Author: Ben Kelly <bkelly@mozilla.com>
Desc: Merge pull request #13966 from wanderview/contacts-onscreen-style

Bug 942398: Do not remove missing styles while scrolling.  r=arcturus

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https://hg.mozilla.org/integration/gaia-central/rev/ae6946373191
Author: Ben Kelly <ben@wanderview.com>
Desc: Bug 942398: Do not remove missing styles while scrolling.