Issue Summary

This is reproducible on Data Center: (yes) 

Steps to Reproduce

1. Goto "Logging and Profiling" page in Confluence DC.
2. Add any fully qualified package name or class name with leading and/or trailing whiteSpaces.
3. Save the entry with any available log level.

Expected Results

Either the input should be deemed as invalid and progress halted OR
Trip the leading and/trailing whitespaces and accept the Log level entry

Actual Results

The entry is accepted, but the Logging and Profiling Page is paralysed/corrupted until RESTART.