ASan: re-enable strict memcmp() checks.

Also, introduce ASan suppressions and use them to suppress a memcmp()
report in system-installed libsqlite.

BUG=178677
TBR=glider@chromium.org

Review URL: https://codereview.chromium.org/1070853002

Cr-Commit-Position: refs/heads/master@{#324448}
3 files changed