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

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https://hg.mozilla.org/integration/gaia-central/rev/ea3f51f1dd28
Author: Cristian Rodriguez <crdlc@tid.es>
Desc: Merge pull request #13789 from crdlc/bug-933561

Bug 933561 - App does not come to foreground if user quickly toggles bet...

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https://hg.mozilla.org/integration/gaia-central/rev/ea6738b201a4
Author: crdlc <crdlc@tid.es>
Desc: Bug 933561 - App does not come to foreground if user quickly toggles between home screen and app