Remove find_matching_node.

FWIW the standard says that equality is undefined behaviour if the Hash
and Pred function objects behave differently. But I think we should
support different hash functions, e.g. so that randomized hash functions
will work.

include/boost/unordered/detail/table.hpp

@@ -728,17 +728,6 @@ namespace boost { namespace unordered { namespace detail {
                 find_node_impl(hash(k), k, this->key_eq());
         }
 
-        node_pointer find_matching_node(iterator n) const
-        {
-            // TODO: Does this apply to C++11?
-            //
-            // For some stupid reason, I decided to support equality comparison
-            // when different hash functions are used. So I can't use the hash
-            // value from the node here.
-    
-            return find_node(get_key(*n));
-        }
-
         // Reserve and rehash
 
         void reserve_for_insert(std::size_t);