Fix type inferencing for bounded generics as method return type

[eric-milles]

Consider the following:

def i = (0..10).getFrom() // "T getFrom()" from "interface Range<T extends Comparable>"

The type of "i" is displayed as Comparable<Integer> when it should be just Integer.

abstract class Abstract<T extends Abstract<T>> {
  T withStuff(value) {
    // ...
    return (T) this
  }
}

class Concrete extends Abstract<Concrete> {
  Concrete withThing(value) {
    // ...
    return this
  }
}

def x,y
new Concrete().withStuff(x).withThing(y)

"withThing" is showing as unknown (underlined) because the return type of "withStuff" is inferred as T, not Concrete.