Compiler generates wrong dispatch code for qualified super reference expression

[axls]

GWT version: 2.8.2
Browser (with version): n/a
Operating System: n/a

---

Steps to reproduce

class Y {
  int foo(){
    return 42;
  }
}

class X extends Y{
  int foo(){
    return 23;
  }

  int bar(){
    Supplier<Integer> s = X.super::foo; // reference to Y.foo
    return s.get();
  }
}

Next code snippet returns 23 instead of 42:

new X().bar();

Known workarounds

Replace method reference with lambda or anonymous class.

[axls]

Patch to review https://gwt-review.googlesource.com/c/gwt/+/20760.