This directive anyway does not make test run twice with OI, and with NI
It only once run the test with specific settings (// LANGUAGE)
and ignores irrelevant (OI or NI tags)
Expression will be checked against expected type later.
Theoretically, this is not very good, but it aligns with the old
inference, plus it helps avoiding multiple type mismatch diagnostics.
And String.length as well.
This is done for JVM interoperability: java.lang.CharSequence is an open class
and has a function 'length()' which should be implemented in subclasses
somehow.
A minor unexpected effect of this is that String.length() is now a compile-time
constant (it wasn't such as a property because properties are not supported in
compile-time constant evaluation)
#KT-3571 Fixed
Ivan Kochurkin