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

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https://hg.mozilla.org/integration/gaia-central/rev/16511add58fa
Author: GaryChen(pychen) <mmm198219@gmail.com>
Desc: Merge pull request #13476 from mpizza/Bug_931229_build

Bug 931229 - With kb set to Greek, move to email field, layout remains G...  r=rudyl.

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https://hg.mozilla.org/integration/gaia-central/rev/3d5ce8b6dcab
Author: mpizza <mmm198219@gmail.com>
Desc: Bug 931229 - With kb set to Greek, move to email field, layout remains Greek and can't switch

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https://hg.mozilla.org/integration/gaia-central/rev/03ddafa229d8
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #13505 from AndreiH/bug936016

Bug 936016 - Re-enable test_cards_view_with_three_apps , test_cards_view...

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https://hg.mozilla.org/integration/gaia-central/rev/dbce16eab32a
Author: Andrei Hutusoru <andreihutusoru@P5069.(none)>
Desc: Bug 936016 - Re-enable test_cards_view_with_three_apps , test_cards_view_kill_app_with_three_apps