Revert "Revert 237280 "Remove TraceController""

components/tracing/child_trace_message_filter.h

Index: components/tracing/child_trace_message_filter.h
diff --git a/components/tracing/child_trace_message_filter.h b/components/tracing/child_trace_message_filter.h
index cbd300f38b01297921c961d9f2bd6a2ae01b94d4..d2aae3b5257c67c27aaa3a467193065594ae6350 100644
--- a/components/tracing/child_trace_message_filter.h
+++ b/components/tracing/child_trace_message_filter.h
@@ -43,6 +43,7 @@ class ChildTraceMessageFilter : public IPC::ChannelProxy::MessageFilter {
   void OnSetWatchEvent(const std::string& category_name,
                        const std::string& event_name);
   void OnCancelWatchEvent();
+  void OnWatchEventMatched();
 
   // Callback from trace subsystem.
   void OnTraceDataCollected(
@@ -53,8 +54,6 @@ class ChildTraceMessageFilter : public IPC::ChannelProxy::MessageFilter {
       const scoped_refptr<base::RefCountedString>& events_str_ptr,
       bool has_more_events);
 
-  void OnTraceNotification(int notification);
-
   IPC::Channel* channel_;
   base::MessageLoopProxy* ipc_message_loop_;