39b7c6e326
Make sure that:
- Compilation with -Pkotlin.incremental.useClasspathSnapshot=true or
-Dkotlin.incremental.classpath.snapshot.enabled=true is incremental
after cache hit.
- Default compilation (using build history files) is non-incremental
after cache hit.
Also unify the related tests into
BuildCacheRelocationIT.testKotlinIncrementalCompilation*. We don't need
corresponding tests in BuildCacheIT because BuildCacheRelocationIT
already covers it.