RFR: 8354988: Separate stderr and stdout in Executor class from jpackage test lib

[Alexander Matveev]

On Thu, 17 Apr 2025 23:47:09 GMT, Alexey Semenyuk <asemenyuk at openjdk.org> wrote:

> Rework Executor class from jpackage test lib to support separate configuration of stdout and stderr streams handling:
>  - New `Executor.discardStdout(boolean)` and `Executor.discardStderr(boolean)` methods enable/disable stdout and stderr streams, respectively;
>  - New `Executor.Result.stdout()` accesses saved stdout stream;
>  - New `Executor.Result.stderr()` accesses saved stderr stream;
>  - `Executor.Result.getOutput()` returns merged stdout and stderr streams. Contents of the stdout go first, contents of the stderr follow;
>  - New `JPackageCommand.discardStdout(boolean)` and `JPackageCommand.discardStderr(boolean)` methods enable/disable stdout and stderr streams produced by jpackage, respectively.
> 
> Additionally:
>  - Streamline `BasicTest.testErrorsAlwaysPrinted()`;
>  - Fix WindowsHelper and Win8301247Test as they stopped working as expected due to reordering the contents of stdout and stderr streams in the merged stream returned by `Executor.Result.getOutput()`.

Looks good.

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Marked as reviewed by almatvee (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/24745#pullrequestreview-2777331746