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
* Clients may call this framework method, but should not override it.
	 * </p>
	 *
	 * @param dlus the number of vertical dialog units
	 * @return the number of pixels
	 */
	protected int convertVerticalDLUsToPixels(int dlus) {
		
		if (fontMetrics == null)
			return 0;
		return convertVerticalDLUsToPixels(fontMetrics, dlus);
	}
	/**
	 * Returns the number of pixels corresponding to the
	 * width of the given number of characters.
	 * <p>
	 * This method may only be called after <code>initializeDialogUnits</code>
	 * has been called.
	 * </p>
	 * <p>
	 * Clients may call this framework method, but should not override it.
	 * </p>
	 *
	 * @param chars the number of characters
	 * @return the number of pixels
	 */
	protected int convertWidthInCharsToPixels(int chars) {
		
		if (fontMetrics == null)
			return 0;