CRM_Utils_System_WordPress::url - Change code-branch for caes "isset($path)&&isset...

CRM_Utils_System_WordPress::url - Change code-branch for caes "isset($path)&&isset($query)"

In the other usages of $script and $base, there's a decision to use $script XOR $base as the effective
base-URL.  However, in this branch, the values are concatenated to form the effective base-URL -- which
shouldn't produce a valid base-URL.  (Note: In this context, we're evaluating conditons of isset($path) and
isset($query) which should have no bearing on the validity of $script or $base as a base-URL.)