Bumping gaia.json for 1 gaia-1_2 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_2/rev/477073e7942a
Author: Jonathan Griffin <jgriffin@mozilla.com>
Desc: Bug 933718 - Disable 2 tests so we can re-open mozilla-b2g26, a=test-only