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

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https://hg.mozilla.org/integration/gaia-central/rev/439b2b10e787
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Merge pull request #14481 from davidflanagan/bug925216

Bug 925216: Add media info display to Gallery; change styles in Video to match r=pdahiya

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https://hg.mozilla.org/integration/gaia-central/rev/e8c59ed2e2cc
Author: Tom Herold <therold@mozilla.com>
Desc: Bug 925216: Add media info display to Gallery; change styles in Video to match

add 1rem more padding on the left for dt and dd elements