Pending the outcome of the discussion on the GitHub issue:
https://github.com/WebAssembly/design/issues/1138

R=clemensh@chromium.org,ahaas@chromium.org

Bug: 
Change-Id: I54a218a93c24cb221b9f0195e2b1abbe6208d8e2
Reviewed-on: https://chromium-review.googlesource.com/735343Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48907}