The conversion instr was being called twice and
the src register was not restored after the shift.

R=joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2527873003
Cr-Commit-Position: refs/heads/master@{#41269}