Bumping gaia.json for 1 gaia-central revision(s)

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https://hg.mozilla.org/integration/gaia-central/rev/8c3555526de2
Author: Julien Wajsberg <felash@gmail.com>
Desc: Bug 913938 - [homescreen] Make the panning a little smoother at the start r=crdlc

Use the defined "pan" function for the first move too.