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

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https://hg.mozilla.org/integration/gaia-central/rev/cb4a640d8978
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Merge pull request #11414 from mcirlanaru/bug_902130

Bug 902130 - [Keyboard] Properly enable the language-associated ... r=davidflanagan

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https://hg.mozilla.org/integration/gaia-central/rev/992c9dd24e1a
Author: Mihai Cirlanaru <mihai@cirlanaru.com>
Desc: Bug 902130 - [Keyboard] Properly enable the language-associated kb layout for Serbian