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

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https://hg.mozilla.org/integration/gaia-central/rev/305745c12aa0
Author: Ryan VanderMeulen <ryanvm@gmail.com>
Desc: Merge pull request #24419 from tauzen/Bug1071510_no_screenshot

Bug 1071510 - [NFC/sharing] Use shrinking* events to handle screenshot in AppWindow, r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/166fd4fbc436
Author: Krzysztof Mioduszewski <kmioduszewski@gmail.com>
Desc: Bug 1071510 - [NFC/sharing] Use shrinking* events to handle screenshot in AppWindow, r=alive
Bumping manifests a=b2g-bump