switch one build to Release mode
switch one build to Release mode

This turns on optimization which allows the compiler to discover more
problems and omit some more warnings.

jlanecox/googletest,jlanecox/googletest,xnagireddy/googletest,fuchsia-mirror/third_party-googletest,google/googletest,empiredan/googletest,google/googletest,xnagireddy/googletest,xnagireddy/googletest,gianricardo/googletest,fuchsia-mirror/third_party-googletest,jlanecox/googletest,antidotcb/googletest,google/googletest,jlanecox/googletest,gianricardo/googletest,google/googletest,antidotcb/googletest,fuchsia-mirror/third_party-googletest,antidotcb/googletest,empiredan/googletest,antidotcb/googletest,xnagireddy/googletest,fuchsia-mirror/third_party-googletest,empiredan/googletest,gianricardo/googletest