[midPoint-git] [Evolveum/midpoint] c37ee2: Add diagnostics to null value serialization issue

[mederly]

  Branch: refs/heads/support-4.0
  Home:   https://github.com/Evolveum/midpoint
  Commit: c37ee211cafe2ed42c636cc67ef598379c054e6d
      https://github.com/Evolveum/midpoint/commit/c37ee211cafe2ed42c636cc67ef598379c054e6d
  Author: Pavol Mederly <mederly at evolveum.com>
  Date:   2021-08-31 (Tue, 31 Aug 2021)

  Changed paths:
    M infra/prism-impl/src/main/java/com/evolveum/midpoint/prism/impl/marshaller/PrismMarshaller.java

  Log Message:
  -----------
  Add diagnostics to null value serialization issue

The message "Neither real nor raw value present in ..." that
occurs e.g. when dumping traces is hard to diagnose. This
experimental code dumps a bit of context to help with that.