Add a test that tests supercalls in traits.

Author: DarkDimius

tests/run/supercalls-traits.scala

@@ -0,0 +1,15 @@
+trait A {
+ def foo = 1
+}
+
+trait B {
+ def foo = 2
+}
+
+class C extends A with B {
+ override def foo = super[A].foo + super[B].foo
+}
+
+object Test {
+ def main(args: Array[String]) = assert(new C().foo == 3)
+}