Let's take a look at two examples; I think they need to handled differently.
== D3.js
This is minimized and has no license statement.
We don't want to imply it's Apache contributed code
I believe this needs a entry in NOTICE.
(an alternative might be to put a LICENSE/NOTCIE file in that directory
- not sure about that)
== Sgvizler.pack.js
This has a copyright license in the file so this is is definitely under the
http://www.apache.org/dev/licensing-howto.html#mod-notice
"it suffices to leave those notices in their original locations."
Andy