RFR 8162876: [TEST_BUG] sun/net/www/protocol/http/HttpInputStream.java fails intermittently

[Svetlana Nikandrova]

Hello,

please review this test clean-up. Test 
sun/net/www/protocol/http/HttpInputStream.java fails intermittently with 
stale threads remaining.
I've done some refactoring to make sure that all request data is read, 
resources are closed and I also hope test is more readable now.
Webrev:
http://cr.openjdk.java.net/~snikandrova/8162876/webrev.00/ 
<http://cr.openjdk.java.net/%7Esnikandrova/8162876/webrev.00/>
Bug:
https://bugs.openjdk.java.net/browse/JDK-8162876

Thank you,
Svetlana