Port 6470ddad

Original commit message:

    This introduces SilenceNaN operator, which makes sure that we only
    store quiet NaNs into holey arrays. We omit the NaN silencing code
    at instruction selection time if the input is an operation that
    cannot possibly produce signalling NaNs.

R=jarin@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com

BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2069883002
Cr-Commit-Position: refs/heads/master@{#36981}