[8u] RFR Backport 8217878: ENVELOPING XML signature no longer works

[Elliott Baron]

Hi,

I'd like to request a review to backport 8217878 to 8u.

Note: this changeset also fixes "8218629: XML Digital Signature throws 
NAMESPACE_ERR exception on OpenJDK 11, works 8/9/10".

Original fix:
https://bugs.openjdk.java.net/browse/JDK-8217878
https://hg.openjdk.java.net/jdk/jdk/rev/d870bb08194a

The original JDK 13 fix did not apply cleanly. I had to make a few minor 
changes outlined below.

org/jcp/xml/dsig/internal/dom/DOMReference:
- Remove Node type parameter from context due to "8046949: Generify the 
javax.xml.crypto API" not in 8u.

org/jcp/xml/dsig/internal/dom/DOMSignatureMethod:
- Context changed in several hunks since we didn't backport "8042967: 
Add variant of DSA Signature algorithms that do not ASN.1 encode the 
signature bytes" to 8u.

org/jcp/xml/dsig/internal/dom/DOMXMLSignature:
- Adding SuppressWarnings annotations back isn't necessary since they 
were removed by "8046949: Generify the javax.xml.crypto API", which was 
not backported to 8u.

8u webrev:
http://cr.openjdk.java.net/~ebaron/jdk8u/JDK-8217878/webrev.00/

Testing: x86_64 build, jdk_tier1, jdk_security tests

Thanks,
Elliott