Fallout: tests. As tests frequently elide things, lots of changes

here.  Some of this may have been poorly rebased, though I tried to be
careful and preserve the spirit of the test.

src/test/run-pass/enum-null-pointer-opt.rs

@@ -16,7 +16,7 @@ use std::mem::size_of;
 use std::rc::Rc;
 use std::sync::Arc;
 
-trait Trait {}
+trait Trait { fn dummy(&self) { } }
 
 fn main() {
     // Functions