RFR: JDK-8317920: JDWP-agent sends broken exception event with onthrow option [v8]

[Johannes Bechberger]

> Fix `onthrow` issue by passing the event info to the `initialize` method.
> 
> This prevents `jdb` from receiving a broken exception event and throwing an internal NullPointerException, upon attaching to the JDWP-agent.

Johannes Bechberger has updated the pull request incrementally with one additional commit since the last revision:

  Add suggested fixes

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/16145/files
  - new: https://git.openjdk.org/jdk/pull/16145/files/35f317e8..278927b9

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=16145&range=07
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16145&range=06-07

  Stats: 3 lines in 3 files changed: 0 ins; 1 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/16145.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16145/head:pull/16145

PR: https://git.openjdk.org/jdk/pull/16145