Bumping gaia.json for 4 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/5130a8241013
Author: Arthur Chen <crh0716@gmail.com>
Desc: Merge pull request #12264 from crh0716/917238

Bug 917238 - Load network.json for supported network types r=evelyn

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https://hg.mozilla.org/integration/gaia-central/rev/d061dca88415
Author: Arthur Chen <crh0716@gmail.com>
Desc: Bug 917238 - Load network.json for supported network types

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https://hg.mozilla.org/integration/gaia-central/rev/76789f5668dd
Author: Jan Jongboom <janjongboom@gmail.com>
Desc: Merge pull request #12396 from comoyo/fix_keyboard_nightly

Bug 920039 - Check if app has manifest in keyboard_helper. r=djf

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https://hg.mozilla.org/integration/gaia-central/rev/a3d4909b5271
Author: Jan Jongboom <janjongboom@gmail.com>
Desc: Bug 920039 - Check if app has manifest in keyboard_helper