RFR: 8307478: Implementation of Prepare to Restrict The Dynamic Loading of Agents [v4]

[Alan Bateman]

> This is the implementation for JEP 451. There are two parts to this:
> 
> 1. A multi-line warning is printed when a JVM TI or Java agent is loaded into a running VM. For JVM TI, the message is printed to stderr from JvmtiAgent::load. For Java agents, it is printed to System.err (as that may be redirected) in the JPLIS (j.l.instrumentation) implementation. This part includes an update to the specs and API docs for this.
> 
> 2. If running with -Djdk.instrument.traceUsage or -Djdk.instrument.traceUsage=true, the calls to the Instrumentation API print a trace message and stack trace.

Alan Bateman has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 10 additional commits since the last revision:

 - Merge
 - Refresh package description
 - Merge
 - Tweak docs
 - Merge
 - Draft docs changes
 - Merge
 - Rename/cleanup
 - Merge
 - Initial commit

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Changes:
  - all: https://git.openjdk.org/jdk/pull/13899/files
  - new: https://git.openjdk.org/jdk/pull/13899/files/cb2c44cc..62363d88

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13899&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13899&range=02-03

  Stats: 14428 lines in 456 files changed: 9053 ins; 2491 del; 2884 mod
  Patch: https://git.openjdk.org/jdk/pull/13899.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13899/head:pull/13899

PR: https://git.openjdk.org/jdk/pull/13899