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

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https://hg.mozilla.org/integration/gaia-central/rev/31e726367409
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Merge pull request #22110 from etiennesegonzac/bug-1043284

Bug 1043284 - Trigger the global search when the app title bar is tapped r=21

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https://hg.mozilla.org/integration/gaia-central/rev/1fe8ec542360
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Bug 1043284 - Trigger the global search when the app title bar is tapped.
Bumping manifests a=b2g-bump