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

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https://hg.mozilla.org/integration/gaia-central/rev/2ef2f64cf74e
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #14956 from altsai/bug948826

add test cases for bug 948826.

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https://hg.mozilla.org/integration/gaia-central/rev/271119b79d5b
Author: Al Tsai[:atsai] <atsai@mozilla.com>
Desc: bug 948826, add prompt testing

clone uitests into uitests-privileged and set it as a privileged app

test
 - contacts
 - geolocation
 - device-storage
 - userMedia

remove unnecessary part in uitests-privielged
skip on desktop because there's no microphone available
Bumping manifests a=b2g-bump