This is a partial revert of e857966edb.
Specifically, behavior is restored in the old backend, which will allow
to support language version 1.3, where this language feature was not
enabled yet. There are no changes in the JVM IR backend, because to
enable JVM IR with LV 1.3, you need to pass the compiler argument
`-Xuse-ir` which is not stable and we don't guarantee anything about it.
#KT-50251
This directory is skipped in JVM IR test generator, so they won't show
up as failed anymore.
Note that only failing tests are moved to oldLanguageVersions/. Tests
which already pass are still being run. It may be useful not to break
them in case we _do_ need to support some pre-1.3 language feature
switches in JVM IR.
Most of these tests used this directive as a way to opt in to a new
language feature, and most of those features are already stable for a
long time, so no opt-in is needed. Some other tests used the directive
to opt out from a language feature, replace those by the `LANGUAGE`
directive. One test used the directive to test behavior that actually
depended on the API version; use `API_VERSION` directive there instead.
- Use direct access to property defined into companion object when
it is possible rather than always use an accessor to access the
property.
- Use direct access will speedup runtime performance.
- Avoid to generate useless accessors for companion properties.
Fix of https://youtrack.jetbrains.com/issue/KT-14258
Ilya Chernikov