Need reviewer: regression in control builds, workaround fix

[Alan Bateman]

Kelly O'Hair wrote:
> Joe,
>
> Looks like I need to undo the removal of the sun/nio/cs/ext classes 
> from rt.jar
> (they supposedly belonged in charsets.jar). Control builds of jdk7-tl 
> are broken.
I agree that backing this out for now is the right thing to do. Also, it 
might not matter anyway because once we move to a modular JDK then the 
legacy image and rt.jar goes away.

-Alan.