IssueTracker

Witnessed for the following code snippet.
```
void f() {}
void run(Runnable r) { r.run(); }
void f() {
  run(new Runnable() {
    @Override
    public void run() { f(); }
  });
}
```
After the call to `r.run()` resolves to `Runnable#run, I try to refine it to the method inside the anonymous class. Converting the resulting PsiMethod to a UMethod returns null consistently.

The culprit appears to be JavaConverter#unwrapElements, which does not have a case for PsiExpressionList. It's not clear whether there are additional missing cases besides this one.