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

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https://hg.mozilla.org/integration/gaia-central/rev/ca5cdbcd3a9e
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #17588 from KevinGrandon/bug_987753_vertical_homescreen_initial

Bug 987753 - Land a vertical homescreen in test_apps

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https://hg.mozilla.org/integration/gaia-central/rev/9da57ffa047b
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 987753 - Land a vertical homescreen in test_apps r=vingtetun
Bumping manifests a=b2g-bump