[es6] silence access-check failure for well-known symbol properties

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index c04488240d8d1d6af1f4992514747a9231c4f859..4e67afe863249ed46593425ba5f1454ca84ac48d 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -1211,6 +1211,11 @@ class Object {
   MUST_USE_RESULT static MaybeHandle<Object> GetProperty(
       LookupIterator* it, LanguageMode language_mode = SLOPPY);
 
+  // GetProperty, but allows custom behaviour when an access check fails
+  MUST_USE_RESULT static MaybeHandle<Object> GetPropertyEx(
+      LookupIterator* it, bool& access_check_failed,
+      LanguageMode language_mode = SLOPPY);

[Toon Verwaest, 2015/10/02 08:05:27]

This declaration can now be dropped.

[caitp (gmail), 2015/10/02 10:01:15]

Acknowledged.

[caitp (gmail), 2015/10/02 10:41:56]

Done.

+
   // Implementation of [[Put]], ECMA-262 5th edition, section 8.12.5.
   MUST_USE_RESULT static MaybeHandle<Object> SetProperty(
       Handle<Object> object, Handle<Name> name, Handle<Object> value,
@@ -8375,6 +8380,11 @@ class Symbol: public Name {
   // be used to designate own properties of objects.
   DECL_BOOLEAN_ACCESSORS(is_private)
 
+  // [is_well_known_symbol]: Whether this is a spec-defined well-known symbol,
+  // or not. Well-known symbols do not throw when an access check fails during
+  // a load.
+  DECL_BOOLEAN_ACCESSORS(is_well_known_symbol)
+
   DECLARE_CAST(Symbol)
 
   // Dispatched behavior.
@@ -8392,6 +8402,7 @@ class Symbol: public Name {
 
  private:
   static const int kPrivateBit = 0;
+  static const int kWellKnownSymbolBit = 1;
 
   const char* PrivateSymbolToName() const;