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

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https://hg.mozilla.org/integration/gaia-central/rev/985cb08fd58b
Author: Douglas Sherk <github@sherk.me>
Desc: Merge pull request #18191 from DouglasSherk/994865-sms-stickyheader

Bug 994865 - [SMS] Move sticky refresh call from updateThread to appendThread if creating a new container. r=julienw

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https://hg.mozilla.org/integration/gaia-central/rev/4b12910992a9
Author: DouglasSherk <github@sherk.me>
Desc: Bug 994865 - [SMS] Make appendThread return whether or not it created a new container, and only sticky.refresh if it did. r=julienw
Bumping manifests a=b2g-bump