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

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https://hg.mozilla.org/integration/gaia-central/rev/2b52e85304b9
Author: Luke Chang <lchang@mozilla.com>
Desc: Merge pull request #21427 from begeeben/1024333_no_recent_app

Bug 1024333 - [v1.4][UX]Cannot turn off recent app page by tapping screen when "No recent app" is display, r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/60dbba3d3e58
Author: Yi-Fan Liao <begeeben@gmail.com>
Desc: Bug 1024333 - [v1.4][UX]Cannot turn off recent app page by tapping screen when "No recent app" is display

* Check if the cardsView is empty and should be closed or not in the onStartEvent event handler.
* Add test for closing empty cardsview by touchstart.
Bumping manifests a=b2g-bump