[9] Review request for 8050478: [macosx] Cursor not updating correctly after closing a modal dialog

[dmitry markov]

Hello,

Could you review a fix for jdk9, please?
    bug: https://bugs.openjdk.java.net/browse/JDK-8050478
    webrev: http://cr.openjdk.java.net/~dmarkov/8050478/webrev.00/

Problem description:
Cursor is not updated correctly after closing a modal dialog. The root 
cause of the issue is lack of a mouse exit event during displaying of 
the modal dialog.

Fix:
It is necessary to generate MouseExited event for the window which is 
going to be blocked by the modal dialog.

Thanks,
Dmitry