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

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https://hg.mozilla.org/integration/gaia-central/rev/66125e417588
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Merge pull request #12597 from davidflanagan/bug877771

Bug 877771: fix to BlobView.getUTF8Text() from Yao Wei r=davidflanagan

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https://hg.mozilla.org/integration/gaia-central/rev/8851153215a4
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Bug 877771: fix to BlobView.getUTF8Text() from Yao Wei r=davidflanagan