Bug 888646 - Update missed use of SimpleManifestSink API. r=trivial

This is a simple follow-up to Bug 887121.
Back out 9a57cd3e5a93:b62548e26499 (bug 865745) for causing an unexpected exception in a mochiperf test
Bug 886618. Part 2: Simplify OOM handling when stealing array buffer data. r=ehsan

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extra : rebase_source : 1343b39cdf4e65af99219da47e778f86d8a38b04