Bumping gaia.json for 2 gaia-1_2 revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_2/rev/8ee4c49f55a1
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Merge pull request #12678 from timdream/revert-bug905889-v1.2

Revert "Merge pull request #12261 from snowmantw/issue905889"

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https://hg.mozilla.org/integration/gaia-1_2/rev/164c08db811e
Author: Timothy Guan-tin Chien <timdream@gmail.com>
Desc: Revert "Merge pull request #12261 from snowmantw/issue905889"

This reverts commit ff5f7fa1a0fc849d9b2e5c325963c6ebd51ccd12.