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

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https://hg.mozilla.org/integration/gaia-central/rev/e64186458e9c
Author: Luke Chang <lchang@mozilla.com>
Desc: Merge pull request #18734 from luke-chang/1002377_stingray_homescreen_template

Bug 1002377 - [Stingray] A template for the homescreen-stingray app, r=evelyn, r=johnhu

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https://hg.mozilla.org/integration/gaia-central/rev/243ec4ec4a0d
Author: Luke Chang <lchang@mozilla.com>
Desc: Bug 1002377 - [Stingray] A template for the homescreen-stingray app
Bumping manifests a=b2g-bump