Bumping gaia.json for 1 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_4/rev/cf69827788cc
Author: Etienne Segonzac <etienne@segonzac.info>
Desc: Merge pull request #18580 from etiennesegonzac/bug-997701-tone-player-channel

Bug 997701 - Set TonePlayer's channel when creating the audi element. r=gsvelto, rik
(cherry picked from commit 3617fa6b6e5e2e3c7a198227d27a12bca830ff0a)
Bumping manifests a=b2g-bump