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

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https://hg.mozilla.org/integration/gaia-central/rev/7725ca500b74
Author: GaryChen(pychen) <mmm198219@gmail.com>
Desc: Merge pull request #14831 from mpizza/Bug_937487_handle_activity

Bug 937487 - Keyboard won't disappear after focusing an input and then l... r=alive.

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https://hg.mozilla.org/integration/gaia-central/rev/df2fb59f6372
Author: mpizza <mmm198219@gmail.com>
Desc: Bug 937487 - Keyboard won't disappear after focusing an input and then launch an activity