RFR: 8345060: Remove Security Manager dependencies from java.security.KeyStore and Identity APIs and implementations [v2]

[Sean Mullan]

> Now that JEP 486 has been integrated, `java.security.KeyStore` and `Identity` API and impl dependencies on `System.getSecurityManager`, `AccessController.doPrivileged` and `AccessControlContext` can be removed.
> 
> Most of the changes are straightforward, although some of the refactoring in `KeyStore` was a bit complex due to having to extract the code from the `PrivilegedAction` subclasses.

Sean Mullan has updated the pull request incrementally with one additional commit since the last revision:

  Fix infinite loop which was causing a few test failures.

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/22401/files
  - new: https://git.openjdk.org/jdk/pull/22401/files/1b23516f..9ee1967c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=22401&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=22401&range=00-01

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/22401.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22401/head:pull/22401

PR: https://git.openjdk.org/jdk/pull/22401