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

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https://hg.mozilla.org/integration/gaia-central/rev/b7fe47fdc072
Author: Greg Weng <snowmantw@gmail.com>
Desc: Merge pull request #12845 from snowmantw/issue919888

Bug 919888 - [Lockscreen] The phone unlock itself if you force turn off the screen before unlock

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https://hg.mozilla.org/integration/gaia-central/rev/eb23477bc370
Author: Greg Weng (snowmantw) <gweng@mozilla.com>
Desc: Bug 919888 - [Lockscreen] The phone unlock itself if you force turn off the screen before unlock