removed some unnecessary stuff from d8's initialization

src/d8-debug.cc

 // Copyright 2008 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 254 matching lines @@
   head_ = head_->next();
   if (head_ == NULL) {
     ASSERT(tail_ == result);
     tail_ = NULL;
   }
   return result;
 }
 
 
 void RemoteDebugger::HandleMessageReceived(char* message) {
+  Locker lock;
   HandleScope scope;
 
   // Print the event details.
   TryCatch try_catch;
   Handle<Object> details =
       Shell::DebugMessageDetails(Handle<String>::Cast(String::New(message)));
   if (try_catch.HasCaught()) {
     Shell::ReportException(&try_catch);
     PrintPrompt();
     return;
   }
   String::Utf8Value str(details->Get(String::New("text")));
   if (str.length() == 0) {
     // Empty string is used to signal not to process this event.
     return;
   }
   if (*str != NULL) {
     printf("%s\n", *str);
   } else {
     printf("???\n");
   }
 
   bool is_running = details->Get(String::New("running"))->ToBoolean()->Value();
   PrintPrompt(is_running);
 }
 
 
 void RemoteDebugger::HandleKeyboardCommand(char* command) {
+  Locker lock;
   HandleScope scope;
 
   // Convert the debugger command to a JSON debugger request.
   TryCatch try_catch;
   Handle<Value> request =
       Shell::DebugCommandToJSONRequest(String::New(command));
   if (try_catch.HasCaught()) {
     v8::String::Utf8Value exception(try_catch.Exception());
     const char* exception_string = Shell::ToCString(exception);
     printf("%s\n", exception_string);
@@ skipping 45 matching lines @@
     }
 
     // Pass the keyboard command to the main thread.
     remote_debugger_->KeyboardCommand(
         i::SmartPointer<char>(i::StrDup(command)));
   }
 }
 
 
 }  // namespace v8