Fix type inferencing for class that indirectly implements Map

[eric-milles]

Consider the following:

abstract class A implements Map<String, Number> {
}
class C extends A {
}

void test(C cee) {
  def x = cee.name
}

The class C supports map-based property access since it indirectly implements java.util.Map. However the inferred type of a property is not correct.

[eric-milles]