hg: jdk/jdk: 8221257: Improve serial number generation mechanism for keytool -gencert

[weijun.wang at oracle.com]

Changeset: b7ebff3e4e69
Author:    weijun
Date:      2019-03-30 16:32 +0800
URL:       http://hg.openjdk.java.net/jdk/jdk/rev/b7ebff3e4e69

8221257: Improve serial number generation mechanism for keytool -gencert
Reviewed-by: xuelei, mullan

! src/java.base/share/classes/sun/security/tools/keytool/CertAndKeyGen.java
! src/java.base/share/classes/sun/security/tools/keytool/Main.java
! src/java.base/share/classes/sun/security/x509/CertificateSerialNumber.java
+ test/jdk/sun/security/tools/keytool/Serial64.java