Bumping gaia.json for 1 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/37bb1a2fe97d
Author: Dale Harvey <dale@arandomurl.com>
Desc: Bug 915137 - Dont error if custom contextmenu data is not defined
Bumping gaia.json for 2 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/f08ee6217ddf
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #12519 from edmoz/Add-uitests-mozId-persona

Add UI Tests mozId tests

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https://hg.mozilla.org/integration/gaia-central/rev/04d84aadd85a
Author: Edwin Wong <edwong@mozilla.com>
Desc: Bug 919615 - Add navigator.mozId automated test, r=zac