[strong] Remove all remainders of strong mode

test/mjsunit/strong/super.js

-// Copyright 2015 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.
-
-// Flags: --strong-mode --allow-natives-syntax
-
-'use strong';
-
-
-function desc(obj, n) {
-  return Object.getOwnPropertyDescriptor(obj, n);
-}
-
-
-(function TestClass() {
-  class C {
-    m() {
-      super.x;
-    }
-    get x() {
-      super.x;
-    }
-    set y(_) {
-      super.x;
-    }
-    static m() {
-      super.x;
-    }
-    static get x() {
-      super.x;
-    }
-    static set y(_) {
-      super.x;
-    }
-  }
-
-  assertEquals(C.prototype, C.prototype.m[%HomeObjectSymbol()]);
-  assertEquals(C.prototype, desc(C.prototype, 'x').get[%HomeObjectSymbol()]);
-  assertEquals(C.prototype, desc(C.prototype, 'y').set[%HomeObjectSymbol()]);
-  assertEquals(C, C.m[%HomeObjectSymbol()]);
-  assertEquals(C, desc(C, 'x').get[%HomeObjectSymbol()]);
-  assertEquals(C, desc(C, 'y').set[%HomeObjectSymbol()]);
-})();
-
-
-(function TestObjectLiteral() {
-  let o = {
-    m() {
-      super.x;
-    },
-    get x() {
-      super.x;
-    },
-    set y(_) {
-      super.x;
-    }
-  };
-
-  assertEquals(o, o.m[%HomeObjectSymbol()]);
-  assertEquals(o, desc(o, 'x').get[%HomeObjectSymbol()]);
-  assertEquals(o, desc(o, 'y').set[%HomeObjectSymbol()]);
-})();