Use "-Xno-check-impl" to suppress checking whether the platform declaration
implementation has the "impl" modifier.
Do not check presence of fake overrides from platform class in the impl class,
otherwise there would be a lot of errors about the fact that
equals/hashCode/toString are not marked with the "impl" modifier
When matching platform and impl classifiers, ensure that each declaration from
the platform class scope is present in the impl class scope.
Note that the presence of the 'impl' modifier is not checked yet
For each platform declaration, there must be at least one impl declaration in
the module with the compatible signature; similarly, for each impl declaration,
there must be at least one platform declaration with the compatible signature.
Note that currently the presence of the 'impl' modifier is not checked yet.
Also, the sad fact is that if you have platform and impl declarations which are
not compatible, you get two errors: on the platform delcaration and on the impl
declaration. This needs to be addressed as well