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

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https://hg.mozilla.org/integration/gaia-central/rev/64c4ab231001
Author: Jonathan Griffin <jgriffin@mozilla.com>
Desc: Merge pull request #17170 from jonallengriffin/disable_test

Bug 982260 - Disable Contacts details_test.js, r=gwagner

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https://hg.mozilla.org/integration/gaia-central/rev/e03af642cf35
Author: Jonathan Griffin <jgriffin@mozilla.com>
Desc: Bug 982260 - Disable Contacts details_test.js, r=gwagner
Bumping manifests a=b2g-bump