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

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https://hg.mozilla.org/integration/gaia-central/rev/f19bde8a79d3
Author: Rudy Lu <me@rudy.lu>
Desc: Merge pull request #13342 from RudyLu/settings/Bug913784-language_keyboard_mapping

Bug 913784 - Language selection should also enable associated built-in
r=gnarf, arthur

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https://hg.mozilla.org/integration/gaia-central/rev/9323e284eb81
Author: Rudy Lu <me@rudy.lu>
Desc: Bug 913784 - Language selection should also enable associated built-in
keyboard layout(s).
 - handle default layouts resetting
 - add unit test for changeDefaultLayouts