[K/N][Tests] Fix crashes when casting to an Obj-C class companion

[edisongz]

^KT-65260

[SvyatoslavScherbina]

Please add tests covering the change.

[SvyatoslavScherbina]

The behavior still doesn't seem entirely right:

NSNumber as NSObject.Companion

such a cast should fail, but it succeeds.

[edisongz]

The behavior still doesn't seem entirely right:

NSNumber as NSObject.Companion

such a cast should fail, but it succeeds.

I have a doubt about this case, corresponding to ObjC.

// This result is YES, ObjC class object is instance of meta class.
BOOL result = [NSNumber isKindOfClass:object_getClass(NSObject.class)]; 

So ThrowTypeCastException branch cannot be reached.

[SvyatoslavScherbina]

The behavior still doesn't seem entirely right:

NSNumber as NSObject.Companion

such a cast should fail, but it succeeds.

I have a doubt about this case, corresponding to ObjC.

// This result is YES, ObjC class object is instance of meta class.
BOOL result = [NSNumber isKindOfClass:object_getClass(NSObject.class)]; 

Yes, but semantically NSNumber as NSObject.Companion is not the same.
[NSNumber isKindOfClass:object_getClass(NSObject.class)] is equivalent to NSNumber is NSObjectMeta, which should be true.
But NSNumber is NSObject.Companion has no equivalent in Objective-C. NSObject.Companion is a class that Kotlin synthesizes to reflect the concept of the class object.

NSNumber is NSNumber.Companion == true contradicts general Kotlin rules.
Consider e.g. the following example:

open class A {
    companion object : AMeta()
}
open class AMeta

open class B : A() {
    companion object : BMeta()
}
open class BMeta : AMeta()

fun main() {
    val bAny: Any = B
    println(bAny is A.Companion)
}

It prints false.
A.Companion is a class with only one instance -- A. So B can't be an instance of A.Companion.
Same with NSObject.Companion and NSNumber: NSNumber cant be an instance of NSObject.Companion, only NSObject is.

[SvyatoslavScherbina]

Thank you for the contribution!
Merged manually as 450bb1c.