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

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https://hg.mozilla.org/integration/gaia-central/rev/b4e4e893a644
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #17148 from flodolo/bug942582_emergencycalltext

Bug 942582 - [System] Improve string for emergency call back mode

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https://hg.mozilla.org/integration/gaia-central/rev/267f5d409238
Author: Francesco Lodolo (:flod) <flod@lodolo.net>
Desc: Bug 942582 - [System] Improve string for emergency call back mode

Updated string by :matej

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https://hg.mozilla.org/integration/gaia-central/rev/3cc816903cce
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 983117 - Disable intermittent failing test, Browser Bookmarks > Add bookmark

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https://hg.mozilla.org/integration/gaia-central/rev/69ca20a7fbcc
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 983117 - Disable intermittent failing test, Browser Bookmarks > Edit bookmark
Bumping manifests a=b2g-bump