[OTS] Remove unused constants
[OTS] Remove unused constants

patch by thakis@chromium.org

R=yusukes@chromium.org

Review URL: https://codereview.chromium.org/24502005

irori/ots,davelab6/ots,irori/ots,anthrotype/ots,khaledhosny/ots,anthrotype/ots,davelab6/ots