RFR: 8319554: Select LogOutput* directly for stdout and stderr [v2]

[Xin Liu]

> This patch skips allocation on C heap and invoking jio_snprintf for stdout and stderr. 
> They are 2 predefined LogOuptuts and can't be deleted. 
> 
> We also check the return value of set_log_config in test_asynclog.cpp. if configuration fails,
> the test will be skipped. We expect tot fix the flaky failures(JDK-8309067).

Xin Liu has updated the pull request incrementally with one additional commit since the last revision:

  Update style according to review feedback.
  
  1. avoid nested indentation.
  2. avoid YODA conditions.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/16543/files
  - new: https://git.openjdk.org/jdk/pull/16543/files/9a8f442d..5e350ab2

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=16543&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16543&range=00-01

  Stats: 52 lines in 2 files changed: 22 ins; 12 del; 18 mod
  Patch: https://git.openjdk.org/jdk/pull/16543.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16543/head:pull/16543

PR: https://git.openjdk.org/jdk/pull/16543