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

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https://hg.mozilla.org/integration/gaia-central/rev/c766bc0d49af
Author: Jan Jongboom <janjongboom@gmail.com>
Desc: Merge pull request #18325 from comoyo/bug992346-master

Bug 992346 - Inline keyboard symbols font. r=RudyL

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https://hg.mozilla.org/integration/gaia-central/rev/c789d15b6937
Author: Jan Jongboom <janjongboom@gmail.com>
Desc: Bug 992346 - Inline keyboard symbols font
Bumping manifests a=b2g-bump