change CS_DONE to CS_DESTROY and add state handler for destroy and tear down critical parts of the channel from this method which is not called until it's impossible for anything to be referencing the channel (after final write lock and before destroying the pool)

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@12986 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/include/switch_core.h

@@ -578,6 +578,8 @@ SWITCH_DECLARE(void) switch_core_session_perform_destroy(_Inout_ switch_core_ses
 */
 #define switch_core_session_destroy(session) switch_core_session_perform_destroy(session, __FILE__, __SWITCH_FUNC__, __LINE__)
 
+SWITCH_DECLARE(void) switch_core_session_destroy_state(switch_core_session_t *session);
+
 /*! 
   \brief Provide the total number of sessions
   \return the total number of allocated sessions