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

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https://hg.mozilla.org/integration/gaia-central/rev/5da7e0b310a5
Author: steveck-chung <schung@mozilla.com>
Desc: Merge pull request #25646 from steveck-chung/system-getScreenshot-for-all

Bug 1072781 - [Window Management] Get screenshot for homescreen app since new getScreenshot API is ready, r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/a4678e1524d4
Author: Steve Chung <schung@mozilla.com>
Desc: Bug 1072781 - [Window Management] Get screenshot for homescreen app since new getScreenshot API is ready, r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/9d6a75f3290d
Author: George <georgeiscoming@gmail.com>
Desc: Merge pull request #25820 from cctuan/1069339

Bug 1069339 - The icons in the cut/copy/paste menu are totally unclear

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https://hg.mozilla.org/integration/gaia-central/rev/aeeb062ffee3
Author: cctuan <georgeiscoming@gmail.com>
Desc: Bug 1069339 - update images for textselection dialog
Bumping manifests a=b2g-bump