DevTools: Capture async stacks for event listeners.

Source/core/inspector/InspectorInstrumentation.idl

Index: Source/core/inspector/InspectorInstrumentation.idl
diff --git a/Source/core/inspector/InspectorInstrumentation.idl b/Source/core/inspector/InspectorInstrumentation.idl
index 02e859136093ef5dfcac6fe7febb38d474b68098..bd610097b603e752ec63d3a0b32b2f2ff1a4b650 100644
--- a/Source/core/inspector/InspectorInstrumentation.idl
+++ b/Source/core/inspector/InspectorInstrumentation.idl
@@ -172,8 +172,17 @@ interface InspectorInstrumentation {
     [Timeline, Inline=FastReturn]
     void didDispatchEvent(const InspectorInstrumentationCookie&);
 
-    [DOMDebugger, Inline=FastReturn]
-    InspectorInstrumentationCookie willHandleEvent(ExecutionContext*, Event*);
+    [Debugger, Inline=FastReturn]
+    void didAddEventListener([Keep] EventTarget*, const AtomicString& eventType, EventListener* listener, bool useCapture);
+
+    [Debugger, Inline=FastReturn]
+    void didRemoveEventListener([Keep] EventTarget*, const AtomicString& eventType, EventListener* listener, bool useCapture);
+
+    [Debugger, Inline=FastReturn]
+    void didRemoveAllEventListeners([Keep] EventTarget*);
+
+    [Debugger, DOMDebugger, Inline=FastReturn]
+    InspectorInstrumentationCookie willHandleEvent([Keep] EventTarget*, const AtomicString& eventType, EventListener* listener, bool useCapture);
 
     [Debugger, Inline=FastReturn]
     void didHandleEvent(const InspectorInstrumentationCookie&);