patch 8.2.3404: Vim9: no error for white space before "("

Problem:    Vim9: no error for white space before "(".
Solution:   Give an error, like in a compiled function.

Author: brammool

src/testdir/test_vim9_func.vim

@@ -467,6 +467,10 @@ def Test_call_varargs()
   MyVarargs('one', 'two', 'three')->assert_equal('one,two,three')
 enddef
 
+def Test_call_white_space()
+  CheckDefAndScriptFailure2(["call Test ('text')"], 'E476:', 'E1068:')
+enddef
+
 def MyDefaultArgs(name = 'string'): string
   return name
 enddef

src/userfunc.c

@@ -4921,13 +4921,16 @@ ex_call(exarg_T *eap)
     // Skip white space to allow ":call func ()".  Not good, but required for
     // backward compatibility.
     startarg = skipwhite(arg);
-    rettv.v_type = VAR_UNKNOWN;	// clear_tv() uses this
-
     if (*startarg != '(')
     {
 	semsg(_(e_missing_paren), eap->arg);
 	goto end;
     }
+    if (in_vim9script() && startarg > arg)
+    {
+	semsg(_(e_no_white_space_allowed_before_str_str), "(", eap->arg);
+	goto end;
+    }
 
     /*
      * When skipping, evaluate the function once, to find the end of the
@@ -4969,6 +4972,7 @@ ex_call(exarg_T *eap)
 	funcexe.partial = partial;
 	funcexe.selfdict = fudi.fd_dict;
 	funcexe.check_type = type;
+	rettv.v_type = VAR_UNKNOWN;	// clear_tv() uses this
 	if (get_func_tv(name, -1, &rettv, &arg, &evalarg, &funcexe) == FAIL)
 	{
 	    failed = TRUE;

src/version.c

@@ -755,6 +755,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3404,
 /**/
     3403,
 /**/