patch 8.2.0626: Vim9: wrong syntax of function in Vim9 script

Problem:    Vim9: wrong syntax of function in Vim9 script.
Solution:   Give error for missing space. Implement :echomsg and :echoerr.
            (closes #5670)
diff --git a/src/vim9.h b/src/vim9.h
index a75e175..f1da323 100644
--- a/src/vim9.h
+++ b/src/vim9.h
@@ -15,6 +15,8 @@
     ISN_EXEC,	    // execute Ex command line isn_arg.string
     ISN_ECHO,	    // echo isn_arg.echo.echo_count items on top of stack
     ISN_EXECUTE,    // execute Ex commands isn_arg.number items on top of stack
+    ISN_ECHOMSG,    // echo Ex commands isn_arg.number items on top of stack
+    ISN_ECHOERR,    // echo Ex commands isn_arg.number items on top of stack
 
     // get and set variables
     ISN_LOAD,	    // push local variable isn_arg.number