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

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https://hg.mozilla.org/integration/gaia-central/rev/704087945f5c
Author: John Hu <johu@mozilla.com>
Desc: Merge pull request #25638 from huchengtw-moz/bug-1090822-change-to-default-mode

Bug 1090822 - [Stingray] let trusted_ui to lock orientation to default m..., r=rexboy

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https://hg.mozilla.org/integration/gaia-central/rev/27a4711d7297
Author: John Hu <johu@mozilla.com>
Desc: Bug 1090822 - [Stingray] let trusted_ui to lock orientation to default mode
Bumping manifests a=b2g-bump