Disable extra checks in Release mode.
Disable extra checks in Release mode.

They caused test failures and performance regressions.

R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/16158002

git-svn-id: b158db1e4b4ab85d4c9e510fdef4b1e8c614b15b@14856 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh