Bumping gaia.json for 2 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/1ee8dfe570fc
Author: Jose M. Cantera <jmcanterafonseca@gmail.com>
Desc: Merge pull request #12769 from gtorodelvalle/contacts-bug-924903-custom-tag

Bug 924903 - [Contacts] Custom tag for mobile, mail an email can be edited but it is not saved

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https://hg.mozilla.org/integration/gaia-central/rev/8b14874dca2d
Author: Germán Toro del Valle <gtorodelvalle@gmail.com>
Desc: Bug 924903 - [Contacts] Custom tag for mobile, mail an email can be edited but it is not saved