patch 8.2.2315: Vim9: "enddef" as dict key misintepreted as function end

Problem:    Vim9: "enddef" as dict key misintepreted as function end.
Solution:   Check for following colon. (closes #7640)

src/testdir/test_vim9_func.vim

@@ -116,6 +116,14 @@ def Test_missing_endfunc_enddef()
   CheckScriptFailure(lines, 'E126:', 2)
 enddef
 
+def Test_enddef_dict_key()
+  var d = {
+    enddef: 'x',
+    endfunc: 'y',
+  }
+  assert_equal({enddef: 'x', endfunc: 'y'}, d)
+enddef
+
 def ReturnString(): string
   return 'string'
 enddef

src/userfunc.c

@@ -3444,8 +3444,10 @@ define_function(exarg_T *eap, char_u *name_arg)
 		;
 
 	    // Check for "endfunction" or "enddef".
+	    // When a ":" follows it must be a dict key; "enddef: value,"
 	    if (checkforcmd(&p, nesting_def[nesting]
-						? "enddef" : "endfunction", 4))
+						? "enddef" : "endfunction", 4)
+		    && *p != ':')
 	    {
 		if (nesting-- == 0)
 		{
@@ -3484,7 +3486,7 @@ define_function(exarg_T *eap, char_u *name_arg)
 	    // not find it.
 	    else if (nesting_def[nesting])
 	    {
-		if (checkforcmd(&p, "endfunction", 4))
+		if (checkforcmd(&p, "endfunction", 4) && *p != ':')
 		    emsg(_(e_mismatched_endfunction));
 	    }
 	    else if (eap->cmdidx == CMD_def && checkforcmd(&p, "enddef", 4))

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2315,
 /**/
     2314,
 /**/