<AWT Dev> [9] Review Request: 7185221 [macosx] Regtest should not throw exception if a suitable display mode found

[Sergey Bylokhov]

Hello.
Please review the fix for jdk 9.
The test modify a supported list of DisplayModes and try to check that IllegalArgumentException will be thrown. But the problem occurs, when the test tries to change a supported DisplayMode which refresh rate is unknown. This happens because we match any refresh rate to a REFRESH_RATE_UNKNOWN.

Bug: https://bugs.openjdk.java.net/browse/JDK-7185221
Webrev can be found at: http://cr.openjdk.java.net/~serb/7185221/webrev.00/webrev
Diff: http://cr.openjdk.java.net/~serb/7185221/webrev.00/diff

-- 
Best regards, Sergey.