RFR: JDK-8297911: Memory leak in JfrUpcalls::on_retransform [v2]

[Justin King]

> JDK-8297911: Memory leak in JfrUpcalls::on_retransform

Justin King 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 two additional commits since the last revision:

 - Merge branch 'openjdk:master' into jfr-on-class-creation-memory-leak
 - Memory leak in JfrUpcalls::on_retransform
   
   Signed-off-by: Justin King <jcking at google.com>

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/11445/files
  - new: https://git.openjdk.org/jdk/pull/11445/files/92e65ddb..54d9dfda

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=11445&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=11445&range=00-01

  Stats: 3474 lines in 165 files changed: 1425 ins; 1050 del; 999 mod
  Patch: https://git.openjdk.org/jdk/pull/11445.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11445/head:pull/11445

PR: https://git.openjdk.org/jdk/pull/11445