RFR: 8303697: ProcessTools doesn't print last line of process output [v3]

[Leonid Mesnik]

> The StreamPumper is fixed to process the last line even it is not finishes with '\n' or '\r'. The test included. Testing with tier1-3 also to verify that tests are not broken.

Leonid Mesnik has updated the pull request incrementally with one additional commit since the last revision:

  comments added

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Changes:
  - all: https://git.openjdk.org/jdk/pull/13034/files
  - new: https://git.openjdk.org/jdk/pull/13034/files/7e0305d1..aa12782b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13034&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13034&range=01-02

  Stats: 7 lines in 1 file changed: 5 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/13034.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/13034/head:pull/13034

PR: https://git.openjdk.org/jdk/pull/13034