RFR: 8263640: hs_err improvement: handle class path longer than O_BUFLEN [v4]

[Calvin Cheung]

> Please review this patch for handling the printing of class path with length longer than O_BUFLEN.
> The bug is also reproducible using the `jcmd VM.command_line`. The new test uses `jcmd` to verify this change.
> 
> Testing: 
> - [x] tiers 1,2.

Calvin Cheung has updated the pull request incrementally with one additional commit since the last revision:

  add a comment

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Changes:
  - all: https://git.openjdk.java.net/jdk/pull/4616/files
  - new: https://git.openjdk.java.net/jdk/pull/4616/files/b4b645cd..52f75f05

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4616&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4616&range=02-03

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4616.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4616/head:pull/4616

PR: https://git.openjdk.java.net/jdk/pull/4616