[8u] RFR 8248214: Add paddings for TaskQueueSuper to reduce false-sharing cache contention

[Zhengyu Gu]

I would like to backport this patch to OpendJDK 8u for parity with 
Oracle 8u281.

The original patch does not apply cleanly.

There is a conflict on copyright year of taskqueue.hpp

- * Copyright (c) 2001, 2018, Oracle and/or its affiliates. All rights 
reserved.
+ * Copyright (c) 2001, 2020, Oracle and/or its affiliates. All rights 
reserved.

Besides, 8u does not have DEFINE_PAD_MINUS_SIZE macro, which is 
introduced by JDK-8049737, that is used to pad the variable. This patch 
imported the macro from 11u.

The original bug: https://bugs.openjdk.java.net/browse/JDK-8248214
The original patch: 
https://hg.openjdk.java.net/jdk-updates/jdk11u/rev/08c734477683


8u webrev: http://cr.openjdk.java.net/~zgu/JDK-8248214-8u/webrev.00/


Thanks,

-Zhengyu