MethodParameters class file format change

[Eric McCorkle]

I don't think anyone is using MethodParameters at this point, but I want
to post this just to be sure.

The latest version of the spec alters the class file format of
MethodParameters attributes.

The latest version can be found here:
http://cr.openjdk.java.net/~abuckley/8misc.pdf

I will be committing patches to tl and hsx which update hotspot and the
langtools tools to reflect this change.  However, this will take some
time to propagate, and may affect anyone using this feature (most
likely, to write tests).

Apologies for any inconvenience,
Eric