Changed the debugger API to allow only one debug event listener to be registe...

src/debug-delay.js

 // 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 345 matching lines @@
 // break points set in this script.
 function UpdateScriptBreakPoints(script) {
   for (var i = 0; i < script_break_points.length; i++) {
     if (script_break_points[i].script_name() == script.name) {
       script_break_points[i].set(script);
     }
   }
 }
 
 
-Debug.addListener = function(listener, opt_data) {
-  if (!IS_FUNCTION(listener)) throw new Error('Parameters have wrong types.');
-  %AddDebugEventListener(listener, opt_data);
+Debug.setListener = function(listener, opt_data) {
+  if (!IS_FUNCTION(listener) && !IS_UNDEFINED(listener) && !IS_NULL(listener)) {
+    throw new Error('Parameters have wrong types.');
+  }
+  %SetDebugEventListener(listener, opt_data);
 };
 
-Debug.removeListener = function(listener) {
-  if (!IS_FUNCTION(listener)) throw new Error('Parameters have wrong types.');
-  %RemoveDebugEventListener(listener);
-};
 
 Debug.breakExecution = function(f) {
   %Break();
 };
 
 Debug.breakLocations = function(f) {
   if (!IS_FUNCTION(f)) throw new Error('Parameters have wrong types.');
   return %GetBreakLocations(f);
 };
 
@@ skipping 1295 matching lines @@
       json += NumberToJSON_(elem);
     } else if (IS_STRING(elem)) {
       json += StringToJSON_(elem);
     } else {
       json += elem;
     }
   }
   json += ']';
   return json;
 }