Bug 88352 Operation supports leaks contexts via action handler
I20050315-1100 Susan, this is a different leak from the one that I reported. Test Case: 1. open text editor 2. close text editor ==> DefaultUndoManager is leaked due to undo/redo actions handlers still holding on to the context.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/IOperationHistory.java
*            info for prompting the user. If an IAdaptable is provided,
	 *            callers are encourated to provide an adapter for the
	 *            org.eclipse.swt.widgets.Shell.class.
	 * 
	 * @return the IStatus indicating whether the undo succeeded.
	 * 
	 * The severity code in the returned status describes whether the operation
	 * succeeded and whether it remains in the history. <code>OK</code>
	 * severity indicates that the undo operation was successful and that the
	 * operation has been placed on the redo history. Listeners will receive the
	 * <code>UNDONE</code> notification.
	 * 
	 * <code>CANCEL</code> severity indicates that the user cancelled the
	 * operation and that the operation remains in the undo history.
	 * <code>ERROR</code> severity indicates that the operation could not
	 * successfully be undone. The operation will remain at its current location
	 * in the history, and callers must explicitly remove it if desired. Any
	 * other severity code is not interpreted by the history, and is simply
	 * passed back to the caller. For all severities other than <code>OK</code>,
	 * listeners will receive the <code>OPERATION_NOT_OK</code> notification
	 * instead of the <code>UNDONE</code> notification.
	 * 
	 * @throws ExecutionException
	 *             if an exception occurred during undo.
	 */
	IStatus undoOperation(IUndoableOperation operation,
			IProgressMonitor monitor, IAdaptable info)
			throws ExecutionException;
}