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

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https://hg.mozilla.org/integration/gaia-central/rev/be50e334ab5b
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #20563 from crdlc/bug-1025855

Bug 1025855 - [Vertical Homescreen] Wrong box shadow for bookmarks in edit mode

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https://hg.mozilla.org/integration/gaia-central/rev/d9a842241d74
Author: crdlc <crdlc@tid.es>
Desc: Bug 1025855 - [Vertical Homescreen] Wrong box shadow for bookmarks in edit mode
Bumping manifests a=b2g-bump