The second argument of add/removeEventListener should be an object, null, or undefined

third_party/WebKit/Source/core/inspector/ThreadDebugger.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/inspector/ThreadDebugger.h"
 
 #include "bindings/core/v8/SourceLocation.h"
 #include "bindings/core/v8/V8Binding.h"
 #include "bindings/core/v8/V8DOMException.h"
 #include "bindings/core/v8/V8DOMTokenList.h"
@@ skipping 325 matching lines @@
   return toDOMWindow(info.GetIsolate(), info[0]);
 }
 
 void ThreadDebugger::setMonitorEventsCallback(
     const v8::FunctionCallbackInfo<v8::Value>& info,
     bool enabled) {
   EventTarget* eventTarget = firstArgumentAsEventTarget(info);
   if (!eventTarget)
     return;
   Vector<String> types = normalizeEventTypes(info);
+  NonThrowableExceptionState exceptionState;
   EventListener* eventListener = V8EventListenerHelper::getEventListener(
       ScriptState::current(info.GetIsolate()),
       v8::Local<v8::Function>::Cast(info.Data()), false,
-      enabled ? ListenerFindOrCreate : ListenerFindOnly);
+      enabled ? ListenerFindOrCreate : ListenerFindOnly, exceptionState);
   if (!eventListener)
     return;
   for (size_t i = 0; i < types.size(); ++i) {
     if (enabled)
       eventTarget->addEventListener(AtomicString(types[i]), eventListener,
                                     false);
     else
       eventTarget->removeEventListener(AtomicString(types[i]), eventListener,
                                        false);
   }
@@ skipping 121 matching lines @@
 void ThreadDebugger::onTimer(TimerBase* timer) {
   for (size_t index = 0; index < m_timers.size(); ++index) {
     if (m_timers[index].get() == timer) {
       m_timerCallbacks[index](m_timerData[index]);
       return;
     }
   }
 }
 
 }  // namespace blink