RFR: 8344060: Remove doPrivileged calls from shared implementation code in the java.desktop module : part 1

[Prasanta Sadhukhan]

Since JEP 486 : Permanently Disable the Security Manager
[https://bugs.openjdk.org/browse/JDK-8338625] is now integrated, calls to java.security.AccessController.doPrivileged are obsolete and can be removed.

This PR takes care of some of the shared-platform files in the java.desktop module to have them removed.

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Commit messages:
 - 8344060: Remove doPrivileged calls from shared implementation code in the java.desktop module : part 1

Changes: https://git.openjdk.org/jdk/pull/22133/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22133&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8344060
  Stats: 470 lines in 26 files changed: 4 ins; 305 del; 161 mod
  Patch: https://git.openjdk.org/jdk/pull/22133.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22133/head:pull/22133

PR: https://git.openjdk.org/jdk/pull/22133