[8u] Review Request: 8170937 Swing apps are slow if displaying from a remote source to many local displays

[Sergey Bylokhov]

Hello.
Please review backport of JDK-8170937 to jdk8u-dev.
Bug: https://bugs.openjdk.java.net/browse/JDK-8170937
Webrev jdk8:  http://cr.openjdk.java.net/~serb/8170937/jdk8/webrev.00/
Webrev jdk12: http://cr.openjdk.java.net/~serb/8170937/webrev.03/

Small difference in jdk12 vs jdk8 exists because of:
 - https://bugs.openjdk.java.net/browse/JDK-8041592
   AWT_Mixing was not ported to jdk8, so no changes in 
FrameBorderCounter.java
 - https://bugs.openjdk.java.net/browse/JDK-8134669
   This fix was not ported to jdk8, so its code was not changed.
 - https://bugs.openjdk.java.net/browse/JDK-8137571
   The fix for HiDPI support was not ported to jdk8, so no code related 
to "scale" was changed/added.

Overall the resulted code in jdk8 is the same as in jdk12, but without 
using of scale factors.

--
Best regards, Sergey.