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

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https://hg.mozilla.org/integration/gaia-central/rev/ae5c954ca1b8
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #15332 from KevinGrandon/bug_959357_search_icon

Bug 959357 - [Rocketbar] Add search icon to rocketbar

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https://hg.mozilla.org/integration/gaia-central/rev/584fca69efcf
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 959357 - [Rocketbar] Add search icon to rocketbar r=pivanov