RFR: 8198626: java/awt/KeyboardFocusmanager/TypeAhead/TestDialogTypeAhead.html fails on mac

[Pankaj Bansal]

Hi All,

Please review the following test only fix for jdk15.
Bug : https://bugs.openjdk.java.net/browse/JDK-8198626
webrev: http://cr.openjdk.java.net/~pbansal/8198626/webrev00/ 
<http://cr.openjdk.java.net/%7Epbansal/8198626/webrev00/>

This test was added to the ProblemList as it was failing continuously    .
I have made some changes to properly dispose the frame to stabilize the 
test. I have run multiple iterations of the test on mach5 and it is 
always passing. Links in JBS.

Regards
Pankaj