Re-target for ES.Next (#3901)

A list of changes:
- 'es2015-subset' profile is deprecated, and an 'es.next' profile is added.
- The default profile is changed to 'es.next'
- Renamed the JERRY_ES2015 guard to JERRY_ESNEXT
- Renamed JERRY_ES2015_BUILTIN_* guards to JERRY_BUILTIN_*
- Moved es2015 specific tests to a new 'es.next' subdirectory
- Updated docs, targets, and test runners to reflect these changes

Resolves #3737.

JerryScript-DCO-1.0-Signed-off-by: Dániel Bátyai dbatyai@inf.u-szeged.hu

tests/jerry/es.next/reflect-set.js

@@ -0,0 +1,68 @@
+// 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.
+
+// Copyright 2014 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var object = {};
+Reflect.set (object, 'property', 'batcat');
+
+assert (object.property === 'batcat');
+
+var array = ['cat', 'cat', 'cat'];
+Reflect.set (array, 2, 'bat');
+
+assert (array[2] === 'bat');
+
+assert (3 === Reflect.set.length);
+
+try {
+  Reflect.set ();
+  assert (false);
+} catch (e) {
+  assert (e instanceof TypeError);
+}
+
+try {
+  Reflect.set (42, 'bat');
+  assert (false);
+} catch (e) {
+  assert (e instanceof TypeError);
+}
+
+try {
+  Reflect.set (null, 'bat');
+  assert (false);
+} catch (e) {
+  assert (e instanceof TypeError);
+}
+
+var target = {};
+var a = { [Symbol.toPrimitive]: function () { return 'bat' } };
+var b = { [Symbol.toPrimitive]: function () { throw 'cat' } };
+assert (Reflect.set (target, a, 42) === true);
+assert (42 === target.bat);
+
+try {
+  Reflect.set (null, 'bat');
+  assert (false);
+} catch (e) {
+  assert (e instanceof TypeError);
+}
+
+var y = [];
+Object.defineProperty (y, 0, {value: 42, configurable: false});
+assert (Reflect.set (y, 'length', 0) === false);
+assert (Reflect.set (y, 'length', 2) === true);