FULL PRODUCT VERSION :
java version "1.8.0_45"
Java(TM) SE Runtime Environment (build 1.8.0_45-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.45-b02, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Darwin unit-714.labs.intellij.net 14.3.0 Darwin Kernel Version 14.3.0: Mon Mar 23 11:59:05 PDT 2015; root:xnu-2782.20.48~5/RELEASE_X86_64 x86_64

A DESCRIPTION OF THE PROBLEM :
The problem is that java application which runs in headless mode doesn't terminate on it's main thread completion under the circumstances below:
* EventQueue.push(new EventQueue()) is called on a system EventQueue
* an event is posted to the EventQueue

ADDITIONAL REGRESSION INFORMATION: 
The same code works fine under os x java6:

java version "1.6.0_65"
Java(TM) SE Runtime Environment (build 1.6.0_65-b14-466.1-11M4716)
Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-466.1, mixed mode)

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Compile and run the application which code is provided above

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The application is successfully terminated
ACTUAL -
The application hangs

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Thread dump (relevant part - not-daemon thread):
"AWT-EventQueue-0@563" prio=6 tid=0xe nid=NA waiting
  java.lang.Thread.State: WAITING
	  at sun.misc.Unsafe.park(Unsafe.java:-1)
	  at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
	  at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
	  at java.awt.EventQueue.getNextEvent(EventQueue.java:554)
	  at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:170)
	  at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
	  at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
	  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
	  at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package org;

import java.awt.*;

public class Xxx {
    public static void main(String[] args) throws Exception {
        System.setProperty("java.awt.headless", "true");
        final EventQueue systemQueue = Toolkit.getDefaultToolkit().getSystemEventQueue();
        // Current java process is successfully terminated if the line below is commented.
        systemQueue.push(new EventQueue());
        EventQueue.invokeAndWait(new Runnable() {
            @Override
            public void run() {
                System.out.println("Activated EDT");
            }
        });
        System.out.println("After EDT activation");
    }
}

---------- END SOURCE ----------