RFR: 8286707: JFR: Don't commit JFR internal jdk.JavaMonitorWait events

[Joakim Nordström]

Changed the JFR chunk rotation lock object to specific internal class. This allows that specific Object.wait() event to be skipped, thus not adding JFR internal noise to recordings. 

# Testing
- jdk_jfr

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Commit messages:
 - 8286707: JFR: Don't commit JFR internal jdk.JavaMonitorWait events
 - 8286707: JFR: Don't commit JFR internal jdk.JavaMonitorWait events
 - 8286707: JFR: Don't commit JFR internal jdk.JavaMonitorWait events
 - 8286707: JFR: Don't commit JFR internal jdk.JavaMonitorWait events

Changes: https://git.openjdk.java.net/jdk/pull/8883/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8883&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8286707
  Stats: 51 lines in 3 files changed: 41 ins; 0 del; 10 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8883.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8883/head:pull/8883

PR: https://git.openjdk.java.net/jdk/pull/8883