Fix mapped arguments legacy argument definition initialization (#4434)

This patch fixes #4432.

JerryScript-DCO-1.0-Signed-off-by: Robert Fancsik frobert@inf.u-szeged.hu

jerry-core/ecma/operations/ecma-arguments-object.c

@@ -137,7 +137,7 @@ ecma_op_create_arguments_object (vm_frame_ctx_shared_args_t *shared_p, /**< shar
 
         ecma_deref_ecma_string (prop_name_p);
 
-        prop_value_p->value = argv_p[i];
+        prop_value_p->value = argv_p[i] == ECMA_VALUE_INITIALIZED ? ECMA_VALUE_UNDEFINED : argv_p[i];
         argv_p[i] = ECMA_VALUE_EMPTY;
       }
     }

tests/jerry/es.next/regression-test-issue-4432.js

@@ -0,0 +1,19 @@
+// Copyright JS Foundation and other contributors, http://js.foundation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+function f(x,x,x) {
+  return arguments[1];
+}
+
+assert(f(1) === undefined);