[11u] RFR: 8226374: Restrict TLS signature schemes and named groups

[Doerr, Martin]

Hi,

JDK-8226374 is backported to 11.0.12-oracle. I'd like to backport it for parity.
It doesn't apply cleanly. I've taken the 13u backport as source because it resolves the wrong backport order with JDK-8242141.

Bug:
https://bugs.openjdk.java.net/browse/JDK-8226374

11u CSR:
https://bugs.openjdk.java.net/browse/JDK-8264555

Original change (JDK14):
https://hg.openjdk.java.net/jdk/jdk/rev/a93b7b28f644

13u backport:
https://github.com/openjdk/jdk13u-dev/commit/384445d2

11u rejected hunks (integrated manually):
http://cr.openjdk.java.net/~mdoerr/8226374_TLS_11u/8226374_TLS_rej.txt

my new 11u backport:
http://cr.openjdk.java.net/~mdoerr/8226374_TLS_11u/webrev.00/

Please review.

Best regards,
Martin