RFR: 8004126: TEST_BUG: com/sun/jdi/BadHandshakeTest.java fails intermittently

[Jaroslav Bachorik]

Please, review this test fix.

Issue : https://bugs.openjdk.java.net/browse/JDK-8004126
Webrev: http://cr.openjdk.java.net/~jbachorik/8004126/webrev.00

The failure was caused by the IOHandler not waiting for the actual 
message stating the the debugee was ready. The patch uses the library 
functions to start the debugee and wait for the actual message to 
appear. Also, it detects problems while starting the debugee and reports 
them instead of failing only when the debugger can not connect.

Thanks,

-JB-