Fix per review comment in https://codereview.chromium.org/1156773002.
Fix per review comment in https://codereview.chromium.org/1156773002.

Forgot to fix this before committing the original change.

TBR=yzshen@chromium.org

Review URL: https://codereview.chromium.org/1151273004

chinmaygarde/mojo,afandria/mojo,chinmaygarde/mojo,chinmaygarde/mojo,jianglu/mojo,chinmaygarde/mojo,jianglu/mojo,chinmaygarde/mojo,afandria/mojo,afandria/mojo,jianglu/mojo,afandria/mojo,chinmaygarde/mojo,chinmaygarde/mojo,afandria/mojo,afandria/mojo,afandria/mojo,jianglu/mojo,jianglu/mojo,jianglu/mojo,chinmaygarde/mojo,jianglu/mojo,afandria/mojo,chinmaygarde/mojo,jianglu/mojo