patch 8.2.1000: get error when leaving Ex mode with :visual

Problem:    Get error when leaving Ex mode with :visual and a CmdLineEnter
            autocommand was used.
Solution:   Reset ex_pressedreturn. (closes #6293)

src/ex_docmd.c

@@ -1895,7 +1895,7 @@ do_one_cmd(
 	p = ea.cmd;
 	while (ASCII_ISALNUM(*p))
 	    ++p;
-	p = vim_strnsave(ea.cmd, (int)(p - ea.cmd));
+	p = vim_strnsave(ea.cmd, p - ea.cmd);
 	ret = apply_autocmds(EVENT_CMDUNDEFINED, p, p, TRUE, NULL);
 	vim_free(p);
 	// If the autocommands did something and didn't cause an error, try
@@ -6215,6 +6215,7 @@ do_exedit(
 						|| eap->cmdidx == CMD_view))
     {
 	exmode_active = FALSE;
+	ex_pressedreturn = FALSE;
 	if (*eap->arg == NUL)
 	{
 	    // Special case:  ":global/pat/visual\NLvi-commands"

src/testdir/test_ex_mode.vim

@@ -166,6 +166,17 @@ func Test_ex_mode_errors()
   endtry
   call assert_equal(1, caught_e565)
   au! InsertCharPre
+
+  new
+  au CmdLineEnter * call ExEnterFunc()
+  func ExEnterFunc()
+
+  endfunc
+  call feedkeys("gQvi\r", 'xt')
+
+  au! CmdLineEnter
+  delfunc ExEnterFunc
+  quit
 endfunc
 
 " vim: shiftwidth=2 sts=2 expandtab

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1000,
 /**/
     999,
 /**/