Fix kotlin.native.IncorrectDereferenceException issue on KMM project

The problem

The problem

Today, we encounter a problem, that is our project use KMM(Kotlin Multiplatform Mobile) for sharing code between Android and iOS, but after iOS side get the object from KMM, and used it on another thread, it will report error, and the app will crash. The error is like below:

Uncaught Kotlin exception: kotlin.native.IncorrectDereferenceException: illegal attempt to access non-shared <kmmobject> from other thread

Solution for the problem

Because we return one object for the method, se the solution for the problem is calling .freeze() method on iosMain before return the object.