Bug 126573 [Dialogs] StatusDialog should extend TrayDialog
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/StatusDialog.java
* Sets the message and image to the given status. 
		 * @param status IStatus or <code>null</code>.
		 * <code>null</code> will set the empty text and no image.
		 */
		public void setErrorStatus(IStatus status) {
			if (status != null && !status.isOK()) {
				String message = status.getMessage();
				if (message != null && message.length() > 0) {
					setText(message);
					setImage(findImage(status));
					setBackground(JFaceColors.getErrorBackground(getDisplay()));
					return;
				}
			}
			setText(""); 	
			setImage(null);
			setBackground(fNormalMsgAreaBackground);
		}
	}
	/**
	 * Creates an instance of a status dialog.
	 * @param parent 
	 * 			the parent Shell of the dialog
	 */
	public StatusDialog(Shell parent) {
		super(parent);
		fLastStatus = new Status(IStatus.OK,Policy.JFACE,IStatus.OK,Util.ZERO_LENGTH_STRING,null);
	}
	/**
	 * Specifies whether status line appears to the left of the buttons