Bug 263207 [CommonNavigator] Improve DnD tracing and add DnD test suite
There are no DnD tests for the Common Navigator. Also, the CNF has many test utility classes (basically stolen from JDT), these should be moved into a lower level area, and it looks like org.eclipse.ui.test.harness is a good place. (Perhaps we can get the JDT to use these identical versions as well so there is only one copy that everyone uses). Finally, the DnD tracing needs to be improved to show more information and show it more concisely.
tests/org.eclipse.ui.tests.navigator/src/org/eclipse/ui/tests/navigator/DisplayWaiter.java
/* State -- possible transitions:
	 * 
	 * STOPPED   -> RUNNING
	 * RUNNING   -> STOPPED
	 * RUNNING   -> IDLE
	 * IDLE      -> RUNNING
	 * IDLE      -> STOPPED
	 */
	private static final int RUNNING= 1 << 1;
	private static final int STOPPED= 1 << 2;
	private static final int IDLE= 1 << 3;
	
	
	private int fState;
	
	private long fNextTimeout;
	
	private Thread fCurrentThread;
	
	private Timeout fCurrentTimeoutState;
	/**
	 * Creates a new instance on the given display and timeout.
	 * 
	 * @param display the display to run the event loop of
	 */
	public DisplayWaiter(Display display) {
		this(display, false);
	}