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.


Built from https://develop.svn.wordpress.org/trunk@28460


git-svn-id: http://core.svn.wordpress.org/trunk@28287 1a063a9b-81f0-0310-95a4-ce76da25c4cd