Implement eval support for functions with arguments lexical env. (#3806)

JerryScript-DCO-1.0-Signed-off-by: Zoltan Herczeg zherczeg.u-szeged@partner.samsung.com

tests/jerry/es2015/function-scope2.js

@@ -0,0 +1,45 @@
+// 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.
+
+var a = 1;
+var b = 2;
+
+function f(x = eval("eval('var a = 3; function b() { return 4 } () => a')"), y = b) {
+  eval("eval('var a = 5; function b() { return 6 }')");
+
+  assert(a === 5);
+  assert(b() === 6);
+
+  assert(x() === 3);
+  assert(y() === 4);
+
+  delete a;
+  delete b;
+
+  assert(a === 3);
+  assert(b() === 4);
+
+  assert(x() === 3);
+  assert(y() === 4);
+
+  delete a;
+  delete b;
+
+  assert(a === 1);
+  assert(b === 2);
+
+  assert(x() === 1);
+  assert(y() === 4);
+}
+f()