RFR 8009581: Xpathexception does not honor initcause()

[Jason Mehrens]

> Alan, David,
> thank you for comments - I also agree with all of them. And as a result v3:
> http://cr.openjdk.java.net/~dmeetry/8009581/webrev.3/
> >> I think this looks better. I assume that since the super.getCause() is
> >> null that there is no need to handle IllegalStateException now.

You can still generate a ISE inside readObject by performing "new XPathException(new Exception()).initCause(null)" in the old code and then reading that in the new patch.  In the new code that line would fail fast.
 
Jason