Removes an unnecessary mutex lock in get_con_from_hdl

changelog.md

@@ -33,6 +33,7 @@ HEAD
 - Improvement: Outgoing TLS connections to servers using the SNI extension to
   choose a certificate will now work. Thank you moozzyk for reporting. 
   Fixes #400
+- Improvement: Removes an unnecessary mutex lock in `get_con_from_hdl`.
 - Cleanup: Asio transport policy has been refactored to remove many Boost
   dependencies. On C++03 compilers the `boost::noncopyable` dependency has been
   removed and the `boost::date_time` dependency has been replaced with the newer

websocketpp/endpoint.hpp

@@ -638,7 +638,6 @@ public:
      * @return the connection_ptr. May be NULL if the handle was invalid.
      */
     connection_ptr get_con_from_hdl(connection_hdl hdl, lib::error_code & ec) {
-        scoped_lock_type lock(m_mutex);
         connection_ptr con = lib::static_pointer_cast<connection_type>(
             hdl.lock());
         if (!con) {