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

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https://hg.mozilla.org/integration/gaia-central/rev/545f4781d6ea
Author: Gregor Wagner <anygregor@gmail.com>
Desc: Merge pull request #12347 from nullaus/bug918583-operator-variant-helper

bug 918583 - bind context to listener used in operator variant apn custo...

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https://hg.mozilla.org/integration/gaia-central/rev/836acc5fb9bb
Author: Ghislain 'Aus' Lacroix <aus@mozilla.com>
Desc: bug 918583

-bind context to listener used in operator variant apn customizer.
-Use mozSettings directly, do not rely on local shorthand variable because of varying contexts.

r=gwagner