Improve code hover for advanced assignment or `instanceof` cases

[eric-milles]

Consider the following:

class Pogo { }
trait Todo { }
void test(Pogo pogo) {
  if (pogo instanceof Todo) {
    pogo // Pogo & Todo
  }
}
@groovy.transform.TypeChecked
void test(flag) {
  def list = flag ? [1] : [""] // ArrayList<Integer or String>
}

Hover for last occurrence of "pogo" shows Pogo and hover for "list" shows ArrayList<? extends Serializeable<? extends Serializeable<Integer>>

[eric-milles]

[eric-milles]