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

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https://hg.mozilla.org/integration/gaia-central/rev/7f9ebc4f6449
Author: Ghislain 'Aus' Lacroix <aus@noiseport.org>
Desc: Merge pull request #24524 from nullaus/bug1074043

bug 1074043 - Listen for new activities and adjust titlebar styling as e...

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https://hg.mozilla.org/integration/gaia-central/rev/443c94c26c68
Author: Ghislain 'Aus' Lacroix <aus@mozilla.com>
Desc: bug 1074043 - Listen for new activities and adjust titlebar styling as expected. r=etienne
Bumping manifests a=b2g-bump