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

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https://hg.mozilla.org/integration/gaia-central/rev/7fc18e9b1de5
Author: Zac <zcampbell@mozilla.com>
Desc: Merge pull request #19378 from zacc/bug_1016216

Bug 1016216 - Re-enable test_active_sync_* on-device tests

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https://hg.mozilla.org/integration/gaia-central/rev/fb70bda4da6e
Author: Zac <zcampbell@mozilla.com>
Desc: Bug 1016216 - Re-enable test_active_sync_* on-device tests

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https://hg.mozilla.org/integration/gaia-central/rev/bc0076c2cfa9
Author: Evan Xd <itoyxd@gmail.com>
Desc: Revert "Bug 1007546 - Visual refresh for Add/Edit event view"

This reverts commit aec6ddd4df64567d7d7113146bebfcd0bc16f6db.
Bumping manifests a=b2g-bump