Bug 57762 [Dialogs] honor the platform button dismissal alignment on Mac and GTK
Button ordering is inverted on these platforms. See Display.getDismissalAlignment() or the equivalent JFace mechansim.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/Dialog.java
/**
	 * Image registry key for question image (value
	 * <code>"dialog_question_image"</code>).
	 * 
	 * @deprecated org.eclipse.swt.widgets.Display.getSystemImage(SWT.ICON_QUESTION)
	 */
	public static final String DLG_IMG_QUESTION = "dialog_question_image"; 
	/**
	 * Image registry key for warning image (value
	 * <code>"dialog_warning_image"</code>).
	 * 
	 * @deprecated use
	 *             org.eclipse.swt.widgets.Display.getSystemImage(SWT.ICON_WARNING)
	 */
	public static final String DLG_IMG_WARNING = "dialog_warning_image"; 
	/**
	 * Image registry key for info message image (value
	 * <code>"dialog_messasge_info_image"</code>).
	 * 
	 * @since 2.0
	 */
	public static final String DLG_IMG_MESSAGE_INFO = "dialog_messasge_info_image"; 
	/**
	 * Image registry key for info message image (value
	 * <code>"dialog_messasge_warning_image"</code>).
	 * 
	 * @since 2.0
	 */
	public static final String DLG_IMG_MESSAGE_WARNING = "dialog_messasge_warning_image"; 
	/**