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

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https://hg.mozilla.org/integration/gaia-central/rev/3e5b95290522
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Merge pull request #19915 from jmcanterafonseca/fix_load_l10n

Bug 1019113 - l10n.js is evaluated multiple times

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https://hg.mozilla.org/integration/gaia-central/rev/c604b9deca43
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Bug 1019113 - l10n.js is evaluated multiple times

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https://hg.mozilla.org/integration/gaia-central/rev/7ac012c3175d
Author: Cristian Rodriguez <crdlc@tid.es>
Desc: Merge pull request #19873 from crdlc/bug-1018852

Bug 1018852 - Mechanism to migrate collections and bookmarks to datastor...

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https://hg.mozilla.org/integration/gaia-central/rev/ce151fd0bb3f
Author: crdlc <crdlc@tid.es>
Desc: Bug 1018852 - Mechanism to migrate collections and bookmarks to datastores
Bumping manifests a=b2g-bump