[SP-1377] - Regression of PRD-5172 - PRPT created in PRD 3.9.3 does not ...

...open in 5.0.5, 5.0.6, 5.0.7 and 5.1 (5.1)

cherry-pick from master of https://github.com/pentaho/pentaho-reporting/commit/93da5108965f05cfa7e95811730dc9244b6335b6