RFR: 8344397: Remove Security Manager dependencies from java.security and sun.security packages

[Sean Mullan]

Now that JEP 486 has been integrated, `java.security` and `sun.security` implementation dependencies on `System.getSecurityManager` and `AccessController.doPrivileged` can be removed. 

This should cover most of the remaining cleanup in the security libraries area. A couple of the `sun.security.action` classes can't be removed yet, as well as a few constants in `sun.security.util.SecurityConstants` and internal `ProtectionDomain` methods until dependencies are removed in other areas. Some additional test cleanup can also be done later.

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Commit messages:
 - More cleanup.
 - Merge
 - Initial cleanup.

Changes: https://git.openjdk.org/jdk/pull/22418/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22418&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8344397
  Stats: 1098 lines in 32 files changed: 39 ins; 868 del; 191 mod
  Patch: https://git.openjdk.org/jdk/pull/22418.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22418/head:pull/22418

PR: https://git.openjdk.org/jdk/pull/22418