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

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https://hg.mozilla.org/integration/gaia-central/rev/4ebe17bdf63c
Author: Wilson Page <wilsonpage@me.com>
Desc: Merge pull request #25722 from patelba/1068918

Bug 1068918 - [Camera] Preview header should be first thing in markup

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https://hg.mozilla.org/integration/gaia-central/rev/9d7c2b077bb1
Author: patelba <bhupendra.patel@yahoo.com>
Desc: Bug 1068918 - [Camera] Preview header should be first thing in markup
Bumping manifests a=b2g-bump