patch 8.2.2771: Vim9: assignment not recognized if declaration was skipped

Problem:    Vim9: assignment not recognized if declaration was skipped.
Solution:   Also recognized an assignment if the variable does not exist.
            (closes #8108)

src/ex_docmd.c

@@ -3483,7 +3483,8 @@ find_ex_command(
 
 	    // Recognize an assignment if we recognize the variable name:
 	    // "g:var = expr"
-	    // "var = expr"  where "var" is a variable name.
+	    // "var = expr"  where "var" is a variable name or we are skipping
+	    // (variable declaration might have been skipped).
 	    if (*eap->cmd == '@')
 		p = eap->cmd + 2;
 	    oplen = assignment_len(skipwhite(p), &heredoc);
@@ -3493,6 +3494,7 @@ find_ex_command(
 			|| *eap->cmd == '&'
 			|| *eap->cmd == '$'
 			|| *eap->cmd == '@'
+			|| eap->skip
 			|| lookup(eap->cmd, p - eap->cmd, TRUE, cctx) == OK)
 		{
 		    eap->cmdidx = CMD_var;

src/testdir/test_vim9_assign.vim

@@ -249,6 +249,18 @@ def Test_assignment()
   END
 enddef
 
+def Test_skipped_assignment()
+  var lines =<< trim END
+      for x in []
+        var i: number = 1
+        while false
+          i += 1
+        endwhile
+      endfor
+  END
+  CheckDefAndScriptSuccess(lines)
+enddef
+
 def Test_assign_unpack()
   var lines =<< trim END
     var v1: number

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2771,
 /**/
     2770,
 /**/