Port 63ea3a50

Original commit message:

    Previously, we used the lowest bit for something else.

R=mvstanton@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/2021133002
Cr-Commit-Position: refs/heads/master@{#36601}