WIP remove TODO for old-lub-glb-object so that tests pass

Still don't know quite what is going on here.

Author: nikomatsakis

src/test/ui/lub-glb/old-lub-glb-object.rs

@@ -2,8 +2,6 @@
 // succeeded but the new code (which is stricter) gives an error.
 //
 // compile-pass
-//
-// TODO -- why does this test pass?
 
 trait Foo<T, U> { }