Better handling of startup and shutdown of the debugger agent

src/debug.h

 // Copyright 2006-2008 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 425 matching lines @@
   static bool HasCommands();
   static void ProcessHostDispatch(void* dispatch);
   static void UpdateActiveDebugger();
   static Handle<Object> Call(Handle<JSFunction> fun,
                              Handle<Object> data,
                              bool* pending_exception);
 
   // Start the debugger agent listening on the provided port.
   static bool StartAgent(int port);
 
+  // Stop the debugger agent.
+  static void StopAgent();
+
   inline static bool EventActive(v8::DebugEvent event) {
     // Currently argument event is not used.
     return !Debugger::compiling_natives_ && Debugger::debugger_active_;
   }
 
   static void set_debugger_active(bool debugger_active) {
     Debugger::debugger_active_ = debugger_active;
   }
   static bool debugger_active() { return Debugger::debugger_active_; }
   static void set_compiling_natives(bool compiling_natives) {
@@ skipping 239 matching lines @@
   }
  private:
   Debug::AddressId id_;
   int reg_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_V8_DEBUG_H_