[inspector] support setTimeout in Debugger.scheduleStepIntoAsync method

src/inspector/v8-debugger-agent-impl.h

Index: src/inspector/v8-debugger-agent-impl.h
diff --git a/src/inspector/v8-debugger-agent-impl.h b/src/inspector/v8-debugger-agent-impl.h
index 100b3218cbe92a9b3a4fda706f494ae74c41c90f..5fa251ca98a7ef3b725c72c58acf3437a916f992 100644
--- a/src/inspector/v8-debugger-agent-impl.h
+++ b/src/inspector/v8-debugger-agent-impl.h
@@ -143,8 +143,6 @@ class V8DebuggerAgentImpl : public protocol::Debugger::Backend {
 
   v8::Isolate* isolate() { return m_isolate; }
 
-  bool shouldBreakInScheduledAsyncTask();
-
  private:
   void enableImpl();
 
@@ -204,8 +202,6 @@ class V8DebuggerAgentImpl : public protocol::Debugger::Backend {
   protocol::HashMap<String16, std::vector<std::pair<int, int>>>
       m_blackboxedPositions;
 
-  std::unique_ptr<ScheduleStepIntoAsyncCallback> m_stepIntoAsyncCallback;
-
   DISALLOW_COPY_AND_ASSIGN(V8DebuggerAgentImpl);
 };