Fix a strict standards warning about passing non-variables by reference.

git-svn-id: https://plugins.svn.wordpress.org/broken-link-checker/trunk@1021474 b8457f37-d9ea-0310-8a92-e5e31aec5664
Minor: Suppress an "unused variable" warning. We must have this variable even if we don't care about it because WP passes hook arguments in a certain order.

git-svn-id: https://plugins.svn.wordpress.org/broken-link-checker/trunk@1021476 b8457f37-d9ea-0310-8a92-e5e31aec5664