Bug 29163 SafeRunnable needs to be accessible in JFace
We need to be able to access the SafeRunnable in JFace in order that some error protection can be added to preferences and properties dialogs.
bundles/org.eclipse.ui.workbench/extensions/org/eclipse/jface/wizard/WizardDialog.java
case IDialogConstants.HELP_ID : {
			helpPressed();
			break;
		} 
		case IDialogConstants.BACK_ID : {
			backPressed();
			break;
		} 
		case IDialogConstants.NEXT_ID : {
			nextPressed();
			break;
		} 
		case IDialogConstants.FINISH_ID : {
			finishPressed();
			break;
		}
		
	}
}
/**
 * Calculates the difference in size between the given
 * page and the page container. A larger page results 
 * in a positive delta.
 *
 * @param page the page
 * @return the size difference encoded
 *   as a <code>new Point(deltaWidth,deltaHeight)</code>
 */
private Point calculatePageSizeDelta(IWizardPage page) {
	Control pageControl = page.getControl();