Port fc53eed1

Original commit message:
    The new operator converts a float32 input to int32 through truncation.

R=ahaas@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=

Review URL: https://codereview.chromium.org/1593333006

Cr-Commit-Position: refs/heads/master@{#33392}