Fix arrow function this binding resolving if environment record is present (#4878)

This patch fixes #4872 and fixes #4876.

JerryScript-DCO-1.0-Signed-off-by: Robert Fancsik robert.fancsik@h-lab.eu

tests/jerry/es.next/regression-test-issue-4872.js

@@ -0,0 +1,35 @@
+// 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 M {
+  get foo() {
+    return this._x;
+  }
+  set foo(x) {
+    this._x = x;
+  }
+}
+
+class T5 extends M {
+  constructor() {
+    (() => super.foo = 20)();
+  }
+}
+
+try {
+  new T5
+  assert(false);
+} catch (e) {
+  assert(e instanceof ReferenceError);
+}

tests/jerry/es.next/regression-test-issue-4876.js

@@ -0,0 +1,36 @@
+// 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 M {
+  constructor() {
+    this._x = 45;
+  }
+
+  get foo() {
+    return this._x;
+  }
+}
+
+class N extends M {
+  constructor(x = () => super.foo) {
+    super();
+    assert(x() === 45);
+  }
+
+  x(x = () => super.foo) {
+    return x();
+  }
+}
+
+assert(new N().x() === 45);