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

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https://hg.mozilla.org/integration/gaia-1_4/rev/8d440070dee9
Author: Julien Wajsberg <felash@gmail.com>
Desc: Bug 1018896 - In Travis, fetch the right version of Firefox in the v1.4 branch r=me a=tests
Bumping manifests a=b2g-bump