2022-March-19 - Prerelease - 2.6.606

Fix IllegalMonitorStateException  in StatPanel. (#10198)

This would happen if the underlying GameData object would get re-assigned while we're holding the read lock on the previous one.

This PR also cleans up some of the related code:
  - Adds an accessor for getCollectedData() so multiple methods don't need to track the isDirty bit, which is now just based on collectedData being null.
  - Removes some unneeded args to Arrays.sort()
  - Cleans up some verbose code with the use of a local variable.