RFR: 8229517: Support for optional asynchronous/buffered logging [v4]

[Xin Liu]

> This patch provides a buffer to store asynchrounous messages and flush them to
> underlying files periodically.

Xin Liu has updated the pull request incrementally with one additional commit since the last revision:

  Revert "fix runtime/logging/RedefineClasses.java crashed with -XX:+AsyncLogging"
  
  This reverts commit 81b2a0cb2a6cf57b1cd0baacdf8c0419f14819b4.
  
  This problem is sidetracked by JDK-8265102.

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/3135/files
  - new: https://git.openjdk.java.net/jdk/pull/3135/files/81b2a0cb..54aadfaf

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3135&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3135&range=02-03

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3135.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3135/head:pull/3135

PR: https://git.openjdk.java.net/jdk/pull/3135