Bumping gaia.json for 3 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/ad97a2789eca
Author: Vivien Nicolas <21@vingtetun.org>
Desc: Bug 920561 - Ensure LazyLoader.load does not slow down app rendering. r=mbudzynski,kgrandon

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https://hg.mozilla.org/integration/gaia-central/rev/bf8cf22d1e58
Author: George <georgeiscoming@gmail.com>
Desc: Merge pull request #12412 from cctuan/920357

Bug 920357 - cancel edit mode by clicking non-icon area

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https://hg.mozilla.org/integration/gaia-central/rev/f70973830452
Author: cctuan <georgeiscoming@gmail.com>
Desc: Bug 920357 - cancel edit mode by clicking not-icon area