Hello,

Please review the fix for jdk9:
    bug: https://bugs.openjdk.java.net/browse/JDK-8130136
    webrev: http://cr.openjdk.java.net/~aivanov/8130136/jdk9/webrev.00/


Problem description:
Sometimes a window fails to repaint when it becomes exposed.

When repaint failure occurs, SetDIBitsToDevice() in GDIBlitLoops_nativeBlit() returns 0 with error 87 ("Parameter Error"). It happens because invalid, already released, hDC is passed to SetDIBitsToDevice().


Root cause:
When a window is disposed, the DCs associated with it are released. The handles can be reused for another window.

A thread disposes the window and releases hDC. At this time, DC handle is reused for another window. When Disposer thread cleans up for a died thread, it tries to release the cached hDC. But that handle is already associated with another window. Thus a valid pair hWnd/hDC becomes invalid: painting to released DC fails.


The fix:
Save both hDC and hWnd in the thread local storage, and pair hDC with hWnd when removing it to avoid accidentally releasing hDC which is already reused for another window.


Regards,
Alexey

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