Bug 26109 [Dialogs] Need a FormData version of the button sizing API
The button sizing API in Dialog assumes the developer wants a GridData. We should promote the FormData version in PathVariablesDialog to Dialog.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/Dialog.java
protected Button getButton(int id) {
	return (Button)buttons.get(new Integer(id));
}
/**
 * Returns the button bar control.
 * <p>
 * Clients may call this framework method, but should not override it.
 * </p>
 *
 * @return the button bar, or <code>null</code> if
 * the button bar has not been created yet
 */
protected Control getButtonBar() {
	return buttonBar;
}
/**
 * Returns the button created when <code>createButton</code> is called 
 * with an ID of <code>IDialogConstants.CANCEL_ID</code>.  If 
 * <code>createButton</code> was never called with this parameter, or 
 * if <code>createButton</code> is overridden, <code>getCancelButton</code>
 * will return <code>null</code>.
 * 
 * @return the cancel button or <code>null</code>
 * 
 * @see createButton
 * @since 2.0
 * @deprecated Use <code>getButton(IDialogConstants.CANCEL_ID)</code> instead.
 * 		This method will be removed soon.
 */
protected Button getCancelButton() {