[d8 Workers] Make Worker prototype read-only

src/d8.cc

 // Copyright 2012 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.
 
 
 // Defined when linking against shared lib on Windows.
 #if defined(USING_V8_SHARED) && !defined(V8_SHARED)
 #define V8_SHARED
 #endif
 
@@ skipping 1126 matching lines @@
           .ToLocalChecked(),
       performance_template);
 
   Local<FunctionTemplate> worker_fun_template =
       FunctionTemplate::New(isolate, WorkerNew);
   Local<Signature> worker_signature =
       Signature::New(isolate, worker_fun_template);
   worker_fun_template->SetClassName(
       String::NewFromUtf8(isolate, "Worker", NewStringType::kNormal)
           .ToLocalChecked());
+  worker_fun_template->ReadOnlyPrototype();
   worker_fun_template->PrototypeTemplate()->Set(
       String::NewFromUtf8(isolate, "terminate", NewStringType::kNormal)
           .ToLocalChecked(),
       FunctionTemplate::New(isolate, WorkerTerminate, Local<Value>(),
                             worker_signature));
   worker_fun_template->PrototypeTemplate()->Set(
       String::NewFromUtf8(isolate, "postMessage", NewStringType::kNormal)
           .ToLocalChecked(),
       FunctionTemplate::New(isolate, WorkerPostMessage, Local<Value>(),
                             worker_signature));
@@ skipping 1312 matching lines @@
 }
 
 }  // namespace v8
 
 
 #ifndef GOOGLE3
 int main(int argc, char* argv[]) {
   return v8::Shell::Main(argc, argv);
 }
 #endif