Emit a console warning when blocking event listener is delayed for too long

third_party/WebKit/Source/core/inspector/InspectorDOMDebuggerAgent.h

Index: third_party/WebKit/Source/core/inspector/InspectorDOMDebuggerAgent.h
diff --git a/third_party/WebKit/Source/core/inspector/InspectorDOMDebuggerAgent.h b/third_party/WebKit/Source/core/inspector/InspectorDOMDebuggerAgent.h
index 45827138f8fff17ef306b1f2515223b33338c445..d06e79bd87d632a861a819ed938cf02cfdaae32d 100644
--- a/third_party/WebKit/Source/core/inspector/InspectorDOMDebuggerAgent.h
+++ b/third_party/WebKit/Source/core/inspector/InspectorDOMDebuggerAgent.h
@@ -40,6 +40,10 @@
 #include "wtf/PassOwnPtr.h"
 #include "wtf/text/WTFString.h"
 
+namespace v8 {
+class Function;
+}
+
 namespace blink {
 
 class Element;
@@ -59,6 +63,7 @@ class CORE_EXPORT InspectorDOMDebuggerAgent final
     WTF_MAKE_NONCOPYABLE(InspectorDOMDebuggerAgent);
 public:
     static void eventListenersInfoForTarget(v8::Isolate*, v8::Local<v8::Value>, V8EventListenerInfoList& listeners);
+    static v8::Local<v8::Function> eventListenerEffectiveFunction(v8::Isolate*, v8::Local<v8::Object> handler);
 
     InspectorDOMDebuggerAgent(v8::Isolate*, InspectorDOMAgent*, V8InspectorSession*);
     ~InspectorDOMDebuggerAgent() override;