Add neg test

Author: odersky

tests/neg/given-eta.scala

@@ -0,0 +1,9 @@
+
+trait D
+   type T
+   def trans(other: T): T
+
+def h(d: D)(given x: d.T)(y: d.T) = (d.trans(x), d.trans(y))
+
+val z = h   // error: no implicit argument of type d.T was found for parameter x of method h
+