RFR: 8286392: Address possibly lossy conversions in jdk.jfr [v2]

[Erik Gahlin]

> Could I have a fix of this lossy conversion issue.
> 
> Testing: jdk/jdk/jfr
> 
> Thanks
> Erik

Erik Gahlin 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 lossy_jdkjfr
 - Initial

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8600/files
  - new: https://git.openjdk.java.net/jdk/pull/8600/files/ca573327..598aa319

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8600&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8600&range=00-01

  Stats: 7706 lines in 219 files changed: 4221 ins; 2119 del; 1366 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8600.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8600/head:pull/8600

PR: https://git.openjdk.java.net/jdk/pull/8600