Bumping gaia.json for 2 gaia-central revision(s)

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https://hg.mozilla.org/integration/gaia-central/rev/9c5d02a1f3cc
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Merge pull request #11972 from hotzenklotz/907965_preview_rotation

Bug 907965 - [Gallery] Rotate thumbnail according to EXIF orientation me... r=davidflanagan

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https://hg.mozilla.org/integration/gaia-central/rev/6da0a99f6e49
Author: Tom Herold <therold@mozilla.com>
Desc: Bug 907965 - [Gallery] Rotate thumbnail according to EXIF orientation metadata