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

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https://hg.mozilla.org/integration/gaia-1_4/rev/9e7ac76747ce
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #17682 from alivedise/bugzilla/988261/hide-utility-tray-on-launchapp

Bug 988261 - Hide utility tray on launchapp event, r=timdream

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https://hg.mozilla.org/integration/gaia-1_4/rev/1729f04a9b74
Author: russnicoletti <rnicoletti@mozilla.com>
Desc: Merge pull request #17721 from russnicoletti/bug987224

Bug 987224 - [B2G][Video]Unable to watch videos in video app after deleting two videos. r=johu

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https://hg.mozilla.org/integration/gaia-1_4/rev/b64ecbd1f099
Author: Cristian Rodriguez <crdlc@tid.es>
Desc: Merge pull request #17319 from crdlc/bug-984399

Bug 984399 - Contacts list is not properly updated when importing a new ...

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https://hg.mozilla.org/integration/gaia-1_4/rev/3fd1e80ddef2
Author: Ryan VanderMeulen <rvandermeulen@mozilla.com>
Desc: Merge pull request #17423 from timdream/keyboard-mempressure-race-master

Bug 984238 - Don't kill the keyboard when when it's being launched +shepherd
Bumping manifests a=b2g-bump