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

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https://hg.mozilla.org/integration/gaia-central/rev/0febdd7dec10
Author: John Hu <johu@mozilla.com>
Desc: Merge pull request #15609 from punamdahiya/Bug962639

Bug962639 - [Gallery] Fix of Select a picture and change orientation to landscape shows parts of previous and next picture r=johnhu

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https://hg.mozilla.org/integration/gaia-central/rev/ad9539b99be9
Author: Punam Dahiya <punamdahiya@yahoo.com>
Desc: Bug962639 - [Gallery] Fix of Select a picture and change orientation to landscape shows parts of previous and next picture r=johnhu
Bumping manifests a=b2g-bump