The original intention of this seemed to have been to enable DEBUG when
NDEBUG was not defined within Google3. Everything since then was just
added to avoid the "#error" below checking for consistency from firing.
Semantics have also shifted along the way. I vote for dropping this.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/1315063007

Cr-Commit-Position: refs/heads/master@{#30591}