Bumping gaia.json for 3 gaia-1_2 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_2/rev/58f78725034a
Author: Zac Campbell <zcampbell@mozilla.com>
Desc: Bug 927404 - Fix reporting for failed gaiatest tests, r=dhunt, a=test-only

Conflicts:
	tests/python/gaia-ui-tests/setup.py

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https://hg.mozilla.org/integration/gaia-1_2/rev/c793f656d893
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #12899 from zacc/bug927002_v1.2

[v1.2] Bug 927002 pin marionette python client to >= 0.6.0

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https://hg.mozilla.org/integration/gaia-1_2/rev/981508e201d7
Author: Zac Campbell <zcampbell@mozilla.com>
Desc: Bug 927002 pin marionette python client to >= 0.6.0