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

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https://hg.mozilla.org/integration/gaia-central/rev/6d6399bfb00b
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #23427 from KevinGrandon/bug_1055713_navigate_current_browser_window

Bug 1055713 - Entering a URL when in a browser window should navigate the current browser window

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https://hg.mozilla.org/integration/gaia-central/rev/b8f26fea0eff
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 1055713 - Entering a URL when in a browser window should navigate the current browser window. r=alive
Bumping manifests a=b2g-bump