[strong] Fix super in strong classes

The functions of strong classes are born non extensible. But, when
the class is created we need to add an own private symbol representing
the [[HomeObject]] slot in the spec.

Like for the hidden_string property, we allow adding private own
symbols to non extensible objects.

BUG=v8:4077
LOG=N
R=rossberg@chromium.org

Review URL: https://codereview.chromium.org/1138603003

Cr-Commit-Position: refs/heads/master@{#28447}

src/isolate.cc

@@ -773,11 +773,18 @@ void Isolate::ReportFailedAccessCheck(Handle<JSObject> receiver) {
 
 
 bool Isolate::IsInternallyUsedPropertyName(Handle<Object> name) {
+  if (name->IsSymbol()) {
+    return Handle<Symbol>::cast(name)->is_private() &&
+           Handle<Symbol>::cast(name)->is_own();
+  }
   return name.is_identical_to(factory()->hidden_string());
 }
 
 
 bool Isolate::IsInternallyUsedPropertyName(Object* name) {
+  if (name->IsSymbol()) {
+    return Symbol::cast(name)->is_private() && Symbol::cast(name)->is_own();
+  }
   return name == heap()->hidden_string();
 }
 

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 --harmony-classes --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()]);
+})();