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

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https://hg.mozilla.org/integration/gaia-central/rev/989491c72232
Author: cctuan <georgeiscoming@gmail.com>
Desc: Bug 962938 - Inconsistent file path in zip file

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https://hg.mozilla.org/integration/gaia-central/rev/9888e443d4ab
Author: Fabrice Desre <fabrice@desre.org>
Desc: Bug 962976 - Use a blacklist to avoid compressing specific file types which are already compressed r=yurenju

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https://hg.mozilla.org/integration/gaia-central/rev/ec0c974e434e
Author: Yuren Ju <yurenju@gmail.com>
Desc: Merge pull request #15961 from yurenju/uncompress-2

Bug 957497 - Allow include of uncompressed data files in the package apps r=@timdream

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https://hg.mozilla.org/integration/gaia-central/rev/50c1ebb651a7
Author: Yuren Ju <yurenju@gmail.com>
Desc: Bug 957497 - Allow include of uncompressed data files in the package apps

Conflicts:
	build/utils-xpc.js
	build/utils.js
Bumping manifests a=b2g-bump