patch 8.2.1127: Vim9: getting a dict member may not work

Problem:    Vim9: getting a dict member may not work.
Solution:   Clear the dict only after copying the item. (closes #6390)
diff --git a/src/testdir/test_vim9_expr.vim b/src/testdir/test_vim9_expr.vim
index a604de2..3bf5780 100644
--- a/src/testdir/test_vim9_expr.vim
+++ b/src/testdir/test_vim9_expr.vim
@@ -1133,6 +1133,9 @@
   let d: dict<number> = g:dict_one
   assert_equal(1, d['one'])
 
+  # getting the one member should clear the dict after getting the item
+  assert_equal('one', #{one: 'one'}.one)
+
   call CheckDefFailure(["let x = g:dict_one.#$!"], 'E1002:')
   call CheckDefExecFailure(["let d: dict<any>", "echo d['a']"], 'E716:')
   call CheckDefExecFailure(["let d: dict<number>", "d = g:list_empty"], 'E1029: Expected dict but got list')
diff --git a/src/version.c b/src/version.c
index d1607ae..b406a69 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1127,
+/**/
     1126,
 /**/
     1125,
diff --git a/src/vim9execute.c b/src/vim9execute.c
index b4acb35..bcacaab 100644
--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -2188,6 +2188,7 @@
 		{
 		    dict_T	*dict;
 		    dictitem_T	*di;
+		    typval_T	temp_tv;
 
 		    tv = STACK_TV_BOT(-1);
 		    if (tv->v_type != VAR_DICT || tv->vval.v_dict == NULL)
@@ -2203,8 +2204,11 @@
 			semsg(_(e_dictkey), iptr->isn_arg.string);
 			goto failed;
 		    }
-		    clear_tv(tv);
+		    // Clear the dict after getting the item, to avoid that it
+		    // make the item invalid.
+		    temp_tv = *tv;
 		    copy_tv(&di->di_tv, tv);
+		    clear_tv(&temp_tv);
 		}
 		break;