#305 Fix for target-getter-only in combination with expressions or const...

...ants
We could change the source level just for core/test to 1.8 (Maven allows to use different levels for main and test). I'm starting to wonder though whether the entire idea is a good one. Mixing several issues in one test case may easily be confusing, so I think we should prefer separate test cases/reproducers whenever possible. Still I wouldn't mind making `@IssueKey` repeatable for the (rare) exceptions.