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

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https://hg.mozilla.org/integration/gaia-central/rev/c307df5aae16
Author: Francisco Jordano <arcturus@ardeenelinfierno.com>
Desc: Merge pull request #11398 from arcturus/contact_list_selectable-2

Bug 901079 - [Contacts] Contacts list should offer a select mode

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https://hg.mozilla.org/integration/gaia-central/rev/6df7529b0aae
Author: Francisco Jordano <arcturus@ardeenelinfierno.com>
Desc: Bug 901079 - [Contacts] Contacts list should offer a select mode