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

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https://hg.mozilla.org/integration/gaia-central/rev/9b3b0d110070
Author: Julien Wajsberg <felash@gmail.com>
Desc: Merge pull request #20012 from julienw/1015867-max-height-composer

Bug 1015867 - [Messages] The editable composer should take more space r=...

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https://hg.mozilla.org/integration/gaia-central/rev/872cf988ad45
Author: Julien Wajsberg <felash@gmail.com>
Desc: Bug 1015867 - [Messages] The editable composer should take more space r=schung
Bumping manifests a=b2g-bump