RFR: 8336332: Rework tests to avoid unrelated stderr output [v9]

[Andy Goryachev]

> This PR removes unrelated `stderr` output in the headless test logs by redirecting it to an in-memory buffer.  Exceptions found in the buffer can be checked against the expected list.
> 
> In the case when any mismatch is detected, whether the type or the number of exceptions of particular type, the accumulated buffer gets dumped to `stderr` and the test fails.
> 
> ## How To
> 
> To redirect stderr and later check the exceptions, surround your code with
> 
> `OutputRedirect.suppressStderr()` and either `OutputRedirect.checkStderr()` or `OutputRedirect.checkAndRestoreStderr()` (ideally, in the `finally` block).
> 
> To simply undo redirection, without checking, call  `OutputRedirect.restoreStderr()`.
> 
> To add the check to all the tests in the file, one can call the above mentioned methods inside  `@BeforeEach` and `@AfterEach`.
> 
> ## Changes
> 
> - added `OutputRedirect` facility
> 
> ## Miscellaneous
> 
> `ErrorLoggingUtiltity` name will be fixed in a followup https://bugs.openjdk.org/browse/JDK-8367995

Andy Goryachev has updated the pull request incrementally with one additional commit since the last revision:

  static

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Changes:
  - all: https://git.openjdk.org/jfx/pull/1897/files
  - new: https://git.openjdk.org/jfx/pull/1897/files/3afa2703..43993624

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx&pr=1897&range=08
 - incr: https://webrevs.openjdk.org/?repo=jfx&pr=1897&range=07-08

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jfx/pull/1897.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1897/head:pull/1897

PR: https://git.openjdk.org/jfx/pull/1897