Introduce a handle zapping setting, and enable it by default for release and debug

src/handles.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 83 matching lines @@
 }
 
 
 void HandleScope::DeleteExtensions(Isolate* isolate) {
   v8::ImplementationUtilities::HandleScopeData* current =
       isolate->handle_scope_data();
   isolate->handle_scope_implementer()->DeleteExtensions(current->limit);
 }
 
 
-#ifdef ENABLE_EXTRA_CHECKS
+#ifdef ENABLE_HANDLE_ZAPPING
 void HandleScope::ZapRange(Object** start, Object** end) {
   ASSERT(end - start <= kHandleBlockSize);
   for (Object** p = start; p != end; p++) {
     *reinterpret_cast<Address*>(p) = v8::internal::kHandleZapValue;
   }
 }
 #endif
 
 
 Address HandleScope::current_level_address(Isolate* isolate) {
@@ skipping 432 matching lines @@
   Handle<InterceptorInfo> interceptor(object->GetNamedInterceptor());
   PropertyCallbackArguments
       args(isolate, interceptor->data(), *receiver, *object);
   v8::Handle<v8::Array> result;
   if (!interceptor->enumerator()->IsUndefined()) {
     v8::NamedPropertyEnumerator enum_fun =
         v8::ToCData<v8::NamedPropertyEnumerator>(interceptor->enumerator());
     LOG(isolate, ApiObjectAccess("interceptor-named-enum", *object));
     result = args.Call(enum_fun);
   }
-#if ENABLE_EXTRA_CHECKS
+#if ENABLE_HANDLE_ZAPPING
   CHECK(result.IsEmpty() || v8::Utils::OpenHandle(*result)->IsJSObject());
 #endif
   return v8::Local<v8::Array>::New(reinterpret_cast<v8::Isolate*>(isolate),
                                    result);
 }
 
 
 // Compute the element keys from the interceptor.
 v8::Handle<v8::Array> GetKeysForIndexedInterceptor(Handle<JSReceiver> receiver,
                                                    Handle<JSObject> object) {
   Isolate* isolate = receiver->GetIsolate();
   Handle<InterceptorInfo> interceptor(object->GetIndexedInterceptor());
   PropertyCallbackArguments
       args(isolate, interceptor->data(), *receiver, *object);
   v8::Handle<v8::Array> result;
   if (!interceptor->enumerator()->IsUndefined()) {
     v8::IndexedPropertyEnumerator enum_fun =
         v8::ToCData<v8::IndexedPropertyEnumerator>(interceptor->enumerator());
     LOG(isolate, ApiObjectAccess("interceptor-indexed-enum", *object));
     result = args.Call(enum_fun);
-#if ENABLE_EXTRA_CHECKS
+#if ENABLE_HANDLE_ZAPPING
     CHECK(result.IsEmpty() || v8::Utils::OpenHandle(*result)->IsJSObject());
 #endif
   }
   return v8::Local<v8::Array>::New(reinterpret_cast<v8::Isolate*>(isolate),
                                    result);
 }
 
 
 Handle<Object> GetScriptNameOrSourceURL(Handle<Script> script) {
   Isolate* isolate = script->GetIsolate();
@@ skipping 322 matching lines @@
   data->next = prev_next_;
   data->limit = prev_limit_;
 #ifdef DEBUG
   handles_detached_ = true;
 #endif
   return deferred;
 }
 
 
 } }  // namespace v8::internal