RFR: 8263640: hs_err improvement: handle class path longer than O_BUFLEN [v2]

[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:

  @iklam comment and removed the @requires vm.cds from the test

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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/b3f9a075..60ecf197

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4616&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4616&range=00-01

  Stats: 5 lines in 2 files changed: 0 ins; 4 del; 1 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