<AWT Dev> [13] RFR 8224830:test/jdk/java/awt/Focus/ModalExcludedWindowClickTest/ModalExcludedWindowClickTest.java fails on linux-x64

[Prasanta Sadhukhan]

Hi All,

Please review a test fix for an issue where it is seen that button click 
actionlistener was not called leading to an exception.

Issue seems to arise from the fact that buttonclick was performed 
without waiting for button to really appear/shown.

Fix is to make the actual execution of the test wait for button to appear.

Bug: https://bugs.openjdk.java.net/browse/JDK-8224830

webrev: http://cr.openjdk.java.net/~psadhukhan/8224830/webrev/

Regards
Prasanta