Bug 35192 Dialog.applyDialogFont should protect itself against null arguments
RC2 Now that many plugins use this method to apply the dialog font to widgets the method should protect itself against null arguments. Normally clients create their widget tree in a method createControl and there are changes that the returned control might be null. Adding a statement Dialog.applyDialogFont (result) with result == null will result in new NPEs.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/Dialog.java
public static int convertHorizontalDLUsToPixels(
		FontMetrics fontMetrics,
		int dlus) {
		
		return (
			fontMetrics.getAverageCharWidth() * dlus
				+ HORIZONTAL_DIALOG_UNIT_PER_CHAR / 2)
			/ HORIZONTAL_DIALOG_UNIT_PER_CHAR;
	}
	/**
	 * Returns the number of pixels corresponding to the
	 * given number of vertical dialog units.
	 * <p>
	 * The required <code>FontMetrics</code> parameter may be created in the 
	 * following way:
	 * <code>
	 * 	GC gc = new GC(control);
	 *	gc.setFont(control.getFont());
	 *	fontMetrics = gc.getFontMetrics();
	 *	gc.dispose();
	 * </code>
	 * </p>
	 *
	 * @param fontMetrics used in performing the conversion
	 * @param dlus the number of vertical dialog units
	 * @return the number of pixels
	 * @since 2.0
	 */
	public static int convertVerticalDLUsToPixels(
		FontMetrics fontMetrics,