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

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https://hg.mozilla.org/integration/gaia-central/rev/fc96abf1e7a5
Author: Francisco Jordano <arcturus@ardeenelinfierno.com>
Desc: Merge pull request #12985 from arcturus/bug-929043

Bug 929043 - [Contacts] Contacts .remove function used broken due to webidl

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https://hg.mozilla.org/integration/gaia-central/rev/e42dbb8175db
Author: Francisco Jordano <arcturus@ardeenelinfierno.com>
Desc: Bug 929043 - [Contacts] Contacts .remove function used broken due to webidl