RFR: Merge jdk

[Mikael Vidstedt]

Merge in jdk-15+14

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Commit messages:
 - Merge jdk
 - 8240866: Typo in JDK-8240820 messes up configure --help
 - 8240340: java/lang/management/ThreadMXBean/Locks.java is buggy
 - 8240881: [BACKOUT] 8222489 jcmd VM.system_properties gives unusable paths on Windows
 - 8239487: Better links generation for system properties found in HTML files
 - 8230117: Remove unused JAR tool classes
 - 8239798: SSLSocket closes socket both socket endpoints on a SocketTimeoutException
 - Merge
 - 8240868: Shenandoah: remove CM-with-UR piggybacking cycles
 - 8240524: Remove explicit type argument in test jdk/java/lang/Boolean/MakeBooleanComparable.java
 - ... and 315 more: https://git.openjdk.java.net/portola/compare/3d4ddf30...a67121be

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - master: https://webrevs.openjdk.java.net/portola/2/webrev.00.0
 - jdk: https://webrevs.openjdk.java.net/portola/2/webrev.00.1

Changes: https://git.openjdk.java.net/portola/pull/2/files
  Stats: 60655 lines in 1370 files changed: 35523 ins; 18931 del; 6201 mod
  Patch: https://git.openjdk.java.net/portola/pull/2.diff
  Fetch: git fetch https://git.openjdk.java.net/portola pull/2/head:pull/2

PR: https://git.openjdk.java.net/portola/pull/2