Fold away the NSS cast_cert_validator.cc path.

All platforms with extensions may assume OpenSSL. This removes the
three-argument form of VerificationResult as it's no longer used.

BUG=519504

Review URL: https://codereview.chromium.org/1365733004

Cr-Commit-Position: refs/heads/master@{#352054}
16 files changed