GitLab

This fixes an issue found by -fsanitize=cfi-derived-cast caused by code that
casts a WDResult<T> pointer to WDDestroyableResult<T>.

BUG=457523
R=caitkp@chromium.org

Review URL: https://codereview.chromium.org/1021043002

Cr-Commit-Position: refs/heads/master@{#321644}