Bumping gaia.json for 4 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/39c1d3c029cd
Author: Cristian Rodriguez <crdlc@tid.es>
Desc: Merge pull request #21483 from crdlc/bug-1035646

Bug 1035646 - [Collection App] Drag icons over edit header like vertical...

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https://hg.mozilla.org/integration/gaia-central/rev/320c011a6cac
Author: crdlc <crdlc@tid.es>
Desc: Bug 1035646 - [Collection App] Drag icons over edit header like vertical home

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https://hg.mozilla.org/integration/gaia-central/rev/c578b6979326
Author: Cristian Rodriguez <crdlc@tid.es>
Desc: Merge pull request #21516 from crdlc/bug-1027250

Bug 1027250 - [Rocketbar] Search suggestions in the Homescreen settings ...

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https://hg.mozilla.org/integration/gaia-central/rev/e36980769e04
Author: crdlc <crdlc@tid.es>
Desc: Bug 1027250 - [Rocketbar] Search suggestions in the Homescreen settings is not consistent with the rest of the UI
Bumping manifests a=b2g-bump