[midPoint-git] [Evolveum/midpoint] 258481: Fix working with ScriptExpressionEvaluationContext

[mederly]

  Branch: refs/heads/support-4.0
  Home:   https://github.com/Evolveum/midpoint
  Commit: 258481653a239bfdcf528429fb10ec1d4aac103a
      https://github.com/Evolveum/midpoint/commit/258481653a239bfdcf528429fb10ec1d4aac103a
  Author: Pavol Mederly <mederly at evolveum.com>
  Date:   2020-03-31 (Tue, 31 Mar 2020)

  Changed paths:
    M model/model-common/src/main/java/com/evolveum/midpoint/model/common/expression/functions/CustomFunctions.java
    M model/model-common/src/main/java/com/evolveum/midpoint/model/common/expression/script/ScriptExpression.java
    M model/model-common/src/main/java/com/evolveum/midpoint/model/common/expression/script/ScriptExpressionEvaluationContext.java
    M model/model-common/src/main/java/com/evolveum/midpoint/model/common/expression/script/ScriptExpressionFactory.java
    M model/model-intest/src/test/resources/mapping/resource-dummy-custom-function-crimson.xml

  Log Message:
  -----------
  Fix working with ScriptExpressionEvaluationContext

The thread-local instance of this context was set up and teared down
with no regards for re-entrance. This caused problems with scripts
that called custom functions more than once: the context went away,
falling back to initialization-time operation result, which is obviously
wrong.

So we removed the fallback (now will fail immediately if no context
is present) and fixed the re-entrance treatment.

This should resolve MID-6145.

(cherry picked from commit 11625b9ed5b1f0cc28253305fbc691af65920b59)