The cache key for comments in `WP_Comment_Query::query()` needs to do `wp_array_slice_assoc( $this->query_vars, array_keys( $defaults ) )` instead of `compact( array_keys( $defaults ) )`. The latter assumes all of those variables are still floating around.

See #22400.



git-svn-id: https://develop.svn.wordpress.org/trunk@28460 602fd350-edb4-49c9-b593-d223f7449a82