Steps to Reproduce

1. Create any implementation of org.zkoss.zk.ui.util.PerformanceMeter (or use performanceMonitor)
2. Register the listener in zk.xml
3. Browse any zul
4. Leave the page

Current Result

No ZK-Client-Receive and/or ZK-Client-Complete header.

Expected Result

At least one header is present.

Debug Information

Cause by ZK-4175

1. https://github.com/zkoss/zk/commit/b361b3ab2e72a4635b5d9148f64fcc7d558c8771#diff-d6bd5b107b7b1cf3580b23ef1a5fe3aff40cfcf41c9ae67c3bb5c449486967efR479
It passes a new object, so headers won't be updated.
2. https://github.com/zkoss/zk/commit/b361b3ab2e72a4635b5d9148f64fcc7d558c8771#diff-d6bd5b107b7b1cf3580b23ef1a5fe3aff40cfcf41c9ae67c3bb5c449486967efR858
This copy-paste typo makes the server won't receive ZK-Client-Complete' anymore.

Workaround