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

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https://hg.mozilla.org/integration/gaia-central/rev/d924dc4bc2ec
Author: Aleh Zasypkin <aleh.zasypkin@gmail.com>
Desc: Merge pull request #22489 from azasypkin/bug-1048204-back-button

Bug 1048204 - The back button seems like pressed even without pressed. r=schung

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https://hg.mozilla.org/integration/gaia-central/rev/a10ba0b355ce
Author: Aleh Zasypkin <azasypkin@mozilla.com>
Desc: Bug 1048204 - The back button seems like pressed even without pressed. r=schung
Bumping manifests a=b2g-bump