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

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https://hg.mozilla.org/integration/gaia-central/rev/5704b1c254bb
Author: Hubert Figuière <hub@figuiere.net>
Desc: Bug 915158 - Add the device host package to the dependencies.

Need so that we can run the test from a device / emulator.

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https://hg.mozilla.org/integration/gaia-central/rev/86136244353c
Author: Ryan VanderMeulen <ryanvm@gmail.com>
Desc: Revert "Merge pull request #13486 from KevinGrandon/settings_desktop_shims"

This reverts commit 91ecaba0e827a3c42c2553b8f308b726707fbdf9, reversing
changes made to 87b955d576b7422befadb85208f9a612153c4d08.