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

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https://hg.mozilla.org/integration/gaia-central/rev/5116c92a2905
Author: Greg Weng <snowmantw@gmail.com>
Desc: Merge pull request #15666 from snowmantw/issue963406-jshint-appwindow

Bug 963406 - [AppWindow][JSHint] Fix jshint errors in AppWindow

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https://hg.mozilla.org/integration/gaia-central/rev/1c7fa75b1bbc
Author: Greg Weng <snowmantw@gmail.com>
Desc: Bug 963406 - [AppWindow][JSHint] Fix jshint errors in AppWindow
Bumping manifests a=b2g-bump