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

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https://hg.mozilla.org/integration/gaia-1_4/rev/9c06ae0e237c
Author: Rudy Lu <me@rudy.lu>
Desc: Merge pull request #20331 from RudyLu/build/Bug1023694-stick_to_b2g30

Build/bug1023694 stick to b2g30.
r=yurenju.

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https://hg.mozilla.org/integration/gaia-1_4/rev/9bd477abd0c0
Author: Rudy Lu <me@rudy.lu>
Desc: Bug 1023694 - The integration test js/python all failed on 1.4 branch
Travis CI.
 - Stick to b2g30 for v1.4 branch.
Bumping manifests a=b2g-bump