<AWT Dev> [9] Review request for 8176490: [macosx] Sometimes NSWindow.isZoomed hangs

[Dmitry Markov]

Hello,

Could you review a fix for jdk9, please?

	bug: https://bugs.openjdk.java.net/browse/JDK-8176490
	webrev: http://cr.openjdk.java.net/~dmarkov/8176490/webrev.00/

Problem description:
On OSX AppKit thread and EDT or main application thread might be blocked when a child window is displayed and its parent is hidden at the same time. AppKit thread performs windows ordering caused by displaying of the child window. It retrieves child windows for the parent window and tries to acquire the monitor inside Window.getOwnedWindows_NoClientCode(). However the monitor is already owned by EDT/main application thread which executes setVisible(false) on the parent window. That thread hangs on invocation of CWrapper.NSWindow.isZoomed() since the function must be executed on AppKit thread.

Fix:
Add a new field isZoomed to CPlatformWindow class. The field will contain information about current zoom state for the window. The method deliverMoveResizeEvent() will update the new field using data from the platform. The invocations of CWrapper.NSWindow.isZoomed() in CPlatformWindow should be replaced with isZoomed field. 

Note: I ran JCK tests on the build with fix and did not observe any new problems.

Thanks,
Dmitry