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

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https://hg.mozilla.org/integration/gaia-central/rev/7b498cd3256b
Author: Fernando Campo <fernando.campo@o2.com>
Desc: Merge pull request #13189 from fcampo/bt-imported-contacts-925858

Bug 925858 - Received contacts from Bluetooth are not shown on the contact list (r=bkelly)

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https://hg.mozilla.org/integration/gaia-central/rev/9e1d85783952
Author: Fernando Campo <fernando.campo@o2.com>
Desc: Bug 925858 - Received contacts from Bluetooth are not shown on the contact list

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https://hg.mozilla.org/integration/gaia-central/rev/ed718153289c
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Merge pull request #13106 from davidflanagan/autocorrect-config2

Bug 884752: make keyboard layouts and autocorrect dictionaries configurable at build time r=rlu,yurneju,pike

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https://hg.mozilla.org/integration/gaia-central/rev/3cbd02547b17
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Bug 884752: configure keyboard layouts and dictionaries at build time

fix test to match

move build-time customization to webapp-manifests.js

refactor keyboard layout build system

address review comments