j2cl

[WASM] Remove monolithic pipeline.

Rename MethodDescriptor.exceptionTypeDescriptors to thrownTypeDescriptors.

Remove obsolete TODO.

[WASM] JsInterop - Exclude some methods, eg., native methods, from causing us to generate the JS prototype.

[J2KT] Add readable/integration test covering varargs of boxed types, both nullable and non-null.