patch 7.4.2119

Problem:    Closures are not supported.
Solution:   Capture variables in lambdas from the outer scope. (Yasuhiro
            Matsumoto, Ken Takata)

src/globals.h

@@ -1658,6 +1658,9 @@ EXTERN time_T time_for_testing INIT(= 0);
 
 /* Abort conversion to string after a recursion error. */
 EXTERN int  did_echo_string_emsg INIT(= FALSE);
+
+/* Used for checking if local variables or arguments used in a lambda. */
+EXTERN int *eval_lavars_used INIT(= NULL);
 #endif
 
 /*