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

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https://hg.mozilla.org/integration/gaia-central/rev/5d3a3e4e765b
Author: Alive.Kuo <alegnadise@gmail.com>
Desc: Merge pull request #22913 from alivedise/attention-window-final

Bug 927862 - Implement AttentionWindow, r=etienne

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https://hg.mozilla.org/integration/gaia-central/rev/e2ee54b2a74d
Author: Alive Kuo <alegnadise@gmail.com>
Desc: Bug 927862 - Implement AttentionWindow
Bumping manifests a=b2g-bump