Fix #3190: Add regression test

Author: OlivierBlanvillain

tests/pos/3190.scala

@@ -0,0 +1,9 @@
+object Test extends App {
+  class Foo
+  class Bar extends Foo
+
+  def overload(implicit foo: Foo): Unit = {}
+  def overload(implicit bar: Bar): Unit = {}
+
+  overload(new Bar)
+}