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

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https://hg.mozilla.org/integration/gaia-central/rev/1d46bd9e998d
Author: Sam Foster <sam@sam-i-am.com>
Desc: Merge pull request #21600 from sfoster/bug-1024440-media-resolution

Bug 1024440 - Rename and modify ImageResolution to handle video files. r=yurenju

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https://hg.mozilla.org/integration/gaia-central/rev/a282e7838fd2
Author: Sam Foster <sfoster@mozilla.com>
Desc: Bug 1024440 - Rename and modify ImageResolution to handle video files

* Includes fix to sort directory listing before processing
Bumping manifests a=b2g-bump