[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 12eba2ba25f4468a172436daf03d85ac8a252f10..1db043ec64aed51519a4a7902b157ddcd8ace230 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -1167,7 +1167,11 @@ class Object {
   MUST_USE_RESULT static inline MaybeHandle<Smi> ToSmi(Isolate* isolate,
                                                        Handle<Object> object);
 
-  MUST_USE_RESULT static MaybeHandle<Object> GetProperty(
+  MUST_USE_RESULT static MaybeHandle<Object> GetPropertyInternal(
+      LookupIterator* it, bool* failedAccessCheck,
+      LanguageMode language_mode = SLOPPY);
+
+  MUST_USE_RESULT static inline MaybeHandle<Object> GetProperty(
       LookupIterator* it, LanguageMode language_mode = SLOPPY);
 
   // Implementation of [[Put]], ECMA-262 5th edition, section 8.12.5.
@@ -1212,6 +1216,10 @@ class Object {
       Handle<Object> object, Handle<Name> name,
       LanguageMode language_mode = SLOPPY);
 
+  MUST_USE_RESULT static inline MaybeHandle<Object> GetPropertyOrFallbackValue(
+      Handle<Object> object, Handle<Name> name, Handle<Object> fallbackValue,
+      LanguageMode language_mode = SLOPPY);
+
   MUST_USE_RESULT static MaybeHandle<Object> GetPropertyWithAccessor(
       LookupIterator* it, LanguageMode language_mode);
   MUST_USE_RESULT static MaybeHandle<Object> SetPropertyWithAccessor(