[defineProperty] Fix non-throwing access check failure

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index e3b8c7d2b93ca6e0df530a700430180617d77bdb..f3c26a9746a9d522f9c41e22ad8795b84e5b0300 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -6507,7 +6507,7 @@ Maybe<bool> JSReceiver::OrdinaryDefineOwnProperty(Isolate* isolate,
     if (!it.HasAccess()) {
       isolate->ReportFailedAccessCheck(it.GetHolder<JSObject>());
       RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, Nothing<bool>());
-      return Just(false);
+      return Just(true);
     }
     it.Next();
   }
@@ -7674,7 +7674,6 @@ Maybe<bool> JSObject::PreventExtensions(Handle<JSObject> object,
       !isolate->MayAccess(handle(isolate->context()), object)) {
     isolate->ReportFailedAccessCheck(object);
     RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, Nothing<bool>());
-    UNREACHABLE();
     RETURN_FAILURE(isolate, should_throw,
                    NewTypeError(MessageTemplate::kNoAccess));
   }
@@ -7822,7 +7821,6 @@ Maybe<bool> JSObject::PreventExtensionsWithTransition(
       !isolate->MayAccess(handle(isolate->context()), object)) {
     isolate->ReportFailedAccessCheck(object);
     RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, Nothing<bool>());
-    UNREACHABLE();
     RETURN_FAILURE(isolate, should_throw,
                    NewTypeError(MessageTemplate::kNoAccess));
   }
@@ -15542,7 +15540,6 @@ Maybe<bool> JSObject::SetPrototypeUnobserved(Handle<JSObject> object,
         !isolate->MayAccess(handle(isolate->context()), object)) {
       isolate->ReportFailedAccessCheck(object);
       RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, Nothing<bool>());
-      UNREACHABLE();

[neis, 2016/01/13 08:54:17]

Did you check if we can RETURN_FAILURE here too?  I'm a bit uneasy about
potentially falling through here.

[Jakob Kummerow, 2016/01/13 12:59:48]

Done.

     }
   } else {
     DCHECK(!object->IsAccessCheckNeeded());