[Typesystem] Invalid error

When writing the following code we get an invalid error on the call to doSomething.

package foo

import org.eclipse.emf.ecore.EObject

class Test {
	new() {
		doSomething(getEObject())
	}

	protected def Parameterised<?> getEObject() {
		null
	}
	
	def <T extends EObject> void doSomething(Parameterised<T> thing) {
		println(thing)
	}
	
	private static class Parameterised<T extends EObject> {}
}

The java equivalent however works without any problems:

package foo;

import org.eclipse.emf.ecore.EObject;

public abstract class JavaTest {
	public JavaTest() {
		doSomething(getEObject());
	}

	protected Parameterised<?> getEObject() {
		return null;
	}
	
	public <T extends EObject> void doSomething(Parameterised<T> thing) {
		System.out.println(thing);
	}
	
	private static class Parameterised<T extends EObject> {}
}

Start by reproducing the Xtend example in the issue and compare its type-checking result with the equivalent Java example. Trace the generic call from getEObject() to doSomething(Parameterised) and confirm the behavior against the reported invalid error; done means the valid call is no longer rejected or the diagnostic is explained by a regression test.