Merge 106846 - Before accessing a frame's script controller in V8 bindings, first check that the ...

Source/WebCore/bindings/v8/PageScriptDebugServer.cpp

 /*
  * Copyright (c) 2011 Google Inc. 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
@@ skipping 58 matching lines @@
 }
 
 PageScriptDebugServer::PageScriptDebugServer()
     : ScriptDebugServer()
     , m_pausedPage(0)
 {
 }
 
 void PageScriptDebugServer::addListener(ScriptDebugListener* listener, Page* page)
 {
+    V8Proxy* proxy = V8Proxy::retrieve(page->mainFrame());
+    if (!proxy)
+        return;
     ScriptController* scriptController = page->mainFrame()->script();
     if (!scriptController->canExecuteScripts(NotAboutToExecuteScript))
         return;
-    V8Proxy* proxy = V8Proxy::retrieve(page->mainFrame());
 
     v8::HandleScope scope;
     v8::Local<v8::Context> debuggerContext = v8::Debug::GetDebugContext();
     v8::Context::Scope contextScope(debuggerContext);
 
     if (!m_listenersMap.size()) {
         ensureDebuggerScriptCompiled();
         ASSERT(!m_debuggerScript.get()->IsUndefined());
         v8::Debug::SetDebugEventListener2(&PageScriptDebugServer::v8DebugEventCallback, v8::External::New(this));
     }
@@ skipping 60 matching lines @@
 }
 
 void PageScriptDebugServer::quitMessageLoopOnPause()
 {
     m_clientMessageLoop->quitNow();
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(JAVASCRIPT_DEBUGGER)