Bug 262222 [Workbench] Workbench.shutdown() doesn't complete due to exception
bundles/org.eclipse.jface/src/org/eclipse/jface/operation/ModalContext.java
*/
		private IRunnableWithProgress runnable;
		/**
		 * The exception thrown by the operation starter.
		 */
		private Throwable throwable;
		/**
		 * The progress monitor used for progress and cancelation.
		 */
		private IProgressMonitor progressMonitor;
		/**
		 * The display used for event dispatching.
		 */
		private Display display;
		/**
		 * Indicates whether to continue event queue dispatching.
		 */
		private volatile boolean continueEventDispatching = true;
		/**
		 * The thread that forked this modal context thread.
		 * 
		 * @since 3.1
		 */
		private Thread callingThread;
		/**
		 * Creates a new modal context.
		 * 
		 * @param operation
		 *            the runnable to run
		 * @param monitor