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

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https://hg.mozilla.org/integration/gaia-central/rev/d54dbabfeeab
Author: Rex KM Lee <rexboy@mozilla.com>
Desc: Merge pull request #19098 from rexboy7/1002345-hsWidget

Bug 1002345 - [homescreen-stingray] initital widget frame support. r=johnhu, tzu-lin

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https://hg.mozilla.org/integration/gaia-central/rev/6310b8b1b4aa
Author: Rex Lee <rexboy@mozilla.com>
Desc: Bug 1002345 - [homescreen-stingray] initital widget manager/factory/window support
Bumping manifests a=b2g-bump