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

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https://hg.mozilla.org/integration/gaia-central/rev/ce3251721969
Author: Florin Strugariu <florin.strugariu@softvision.ro>
Desc: Merge pull request #25818 from davehunt/bug1074117-clock

Bug 1074117 - Use expected conditions and optimise element lookups in clock app object

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https://hg.mozilla.org/integration/gaia-central/rev/f4de3cf9da06
Author: Dave Hunt <dave.hunt@gmail.com>
Desc: Bug 1074117 - Use expected conditions where appropriate and optimise element lookups in clock app object. r=fstrugariu
Bumping manifests a=b2g-bump