[v3] Minimally exercise the other alias_decls in <type_traits>

[Mike Stump]

On Oct 15, 2014, at 2:45 AM, Jonathan Wakely <jwakely@redhat.com> wrote:
> On 15/10/14 10:44 +0100, Jonathan Wakely wrote:
>> We might also want to consider a global s/gnu++0x/gnu++11/ some day.
> 
> One reason for doing that replacement is that I keep copying existing
> tests and then having to change it, and I'm lazy!

Lazy is fine, doing 1000 instead of 500 is only a hair more work when we do them all in mass.  I like constancy, so I actually prefer not changing them (til all are changed).