[inspector] introduced debug::SetAsyncTaskListener

src/debug/debug.h

Index: src/debug/debug.h
diff --git a/src/debug/debug.h b/src/debug/debug.h
index ae3f48efd5e1af6d1374e754fbde7c89c60dc67f..310b4cd6981a5dac5c33a85f8c61a7237e3228b6 100644
--- a/src/debug/debug.h
+++ b/src/debug/debug.h
@@ -466,6 +466,8 @@ class Debug {
 
   int NextAsyncTaskId(Handle<JSObject> promise);
 
+  void SetAsyncTaskListener(debug::AsyncTaskListener listener, void* data);
+
   // Returns whether the operation succeeded. Compilation can only be triggered
   // if a valid closure is passed as the second argument, otherwise the shared
   // function needs to be compiled already.
@@ -661,6 +663,9 @@ class Debug {
 
   v8::Debug::MessageHandler message_handler_;
 
+  debug::AsyncTaskListener async_task_listener_ = nullptr;
+  void* async_task_listener_data_ = nullptr;
+
   static const int kQueueInitialSize = 4;
   base::Semaphore command_received_;  // Signaled for each command received.
   LockingCommandMessageQueue command_queue_;