Fix ecma_op_resolve_reference_base for super object bound lexical environments (#2668)

All ECMA_LEXICAL_ENVIRONMENT_SUPER_OBJECT_BOUND type lexical environments should return their outer reference during resolving syntactic reference.
This patch fixes #2666.

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

tests/jerry/es2015/regression-test-issue-2666.js

@@ -0,0 +1,23 @@
+// 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.
+
+class C {
+  static D () {
+    return 5;
+  }
+}
+
+class D extends C {}
+
+assert (D.D () === 5);