<AWT Dev> [9] Review Request: 8078115 Applets now require "modifyThread" permission to exit on windows

[Sergey Bylokhov]

Hello.
Please review a small fix for jdk 9.
After one of the latest fix, we lost an ability to change the priority 
of our toolkit thread with default permissions. We have to use 
doPrivileged block for this(we already do this on linux/osx)

Bug: https://bugs.openjdk.java.net/browse/JDK-8078115
Webrev can be found at: http://cr.openjdk.java.net/~serb/8078115/webrev.00

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Best regards, Sergey.