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

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https://hg.mozilla.org/integration/gaia-central/rev/f13f22397084
Author: Greg Weng <snowmantw@gmail.com>
Desc: Merge pull request #12537 from snowmantw/issue919850

Bug 919850 - [LockScreen] Unlock the phone only after user release the handle

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https://hg.mozilla.org/integration/gaia-central/rev/cbe0956163e9
Author: Greg Weng (snowmantw) <gweng@mozilla.com>
Desc: Bug 919850 - [LockScreen] Unlock the phone only after user release the handle.