RFR: 8252117: com/sun/jdi/BadHandshakeTest.java failed with "ConnectException: Connection refused: connect"

[Alex Menkov]

Please review the fix for BadHandshakeTest.
Summary:
The test verifies that bad (testcase1) or incomplete (testcase2) handshake does not cause debuggee termination.
To check this it tries to attach to the debuggee again (connect in testcase2 is also verification for testcase1)

The fix adds reply logic to the last attach (similar to retry logic in testcase2)

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Commit messages:
 - 8252117: com/sun/jdi/BadHandshakeTest.java failed with "ConnectException: Connection refused: connect"

Changes: https://git.openjdk.java.net/jdk/pull/789/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=789&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8252117
  Stats: 45 lines in 1 file changed: 28 ins; 5 del; 12 mod
  Patch: https://git.openjdk.java.net/jdk/pull/789.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/789/head:pull/789

PR: https://git.openjdk.java.net/jdk/pull/789