Revert of Don't use barcodes in ProtocolPerfTests

remoting/host/client_session.h

Index: remoting/host/client_session.h
diff --git a/remoting/host/client_session.h b/remoting/host/client_session.h
index 8f10358b016f6b4d3d9ad857dc4e9288eda5aa3c..96e177fca209b03ed68e8b4b3bec1355a65eb8e4 100644
--- a/remoting/host/client_session.h
+++ b/remoting/host/client_session.h
@@ -140,10 +140,6 @@
     return client_capabilities_.get();
   }
 
-  void SetEventTimestampsSourceForTests(
-      scoped_refptr<protocol::InputEventTimestampsSource>
-          event_timestamp_source);
-
  private:
   // Creates a proxy for sending clipboard events to the client.
   std::unique_ptr<protocol::ClipboardStub> CreateClipboardProxy();
@@ -241,9 +237,6 @@
   // then it's stored in |pending_video_layout_message_|.
   std::unique_ptr<protocol::VideoLayout> pending_video_layout_message_;
 
-  scoped_refptr<protocol::InputEventTimestampsSource>
-      event_timestamp_source_for_tests_;
-
   // Used to disable callbacks to |this| once DisconnectSession() has been
   // called.
   base::WeakPtrFactory<ClientSessionControl> weak_factory_;