[9] RFR: 8130041: TsacertOptionTest.java intermittently fails on Mac

[Artem Smotrakov]

Hello,

Please review this fix for TsacertOptionTest.java test.

The test fails intermittently on some Macs. It starts a local TSA 
service which is actually an HTTP server. Then, it runs jarsigner which 
uses this local TSA service. The failure happens on some Macs due to 
system network settings. It seems that on such machines jarsigner tries 
to connect to local TSA via proxy that can't redirect a request to TSA. 
The fix updates the test to reset a couple of system properties for 
proxy settings.

The test passes with this patch. There are some other tests which use a 
local TSA in sun/security/tools/jarsigner, but they don't seem to be 
affected by the problem.

Webrev: http://cr.openjdk.java.net/~asmotrak/8130041/webrev.00/
Bug: https://bugs.openjdk.java.net/browse/JDK-8130041

Artem