reflect bug: NewZeroValue was refusing to create slices.
as far as I can tell there's no reason not to.

the Nillable test was succeeding because NewZeroValue
returned the nil interface value and the type guard
was letting it through.  the only change in the test is
more detail in the print.

R=r
DELTA=8  (0 added, 7 deleted, 1 changed)
OCL=29124
CL=29126
diff --git a/src/lib/reflect/all_test.go b/src/lib/reflect/all_test.go
index 8d4ea48..ec77007 100644
--- a/src/lib/reflect/all_test.go
+++ b/src/lib/reflect/all_test.go
@@ -543,7 +543,7 @@
 		ty := reflect.ParseTypeString("", ts);
 		v := reflect.NewZeroValue(ty);
 		if nilable, ok := v.(Nillable); !ok {
-			t.Errorf("%s is not nilable; should be", ts)
+			t.Errorf("%s %T is not nilable; should be", ts, v)
 		}
 	}
 	// Check the implementations