Bug 187796 [KeyBindings] IBindingService cannot return best active bindings for a ParameterizedCommand
IBindingService only supports getBestActiveBindingFor(final String commandId) ... there must be an equivalent method for ParameterizedCommands PW
bundles/org.eclipse.jface/src/org/eclipse/jface/bindings/BindingManager.java
/**
	 * A cache of the bindings previously computed by this manager. This value
	 * may be empty, but it is never <code>null</code>. This is a map of
	 * <code>CachedBindingSet</code> to <code>CachedBindingSet</code>.
	 */
	private Map cachedBindings = new HashMap();
	/**
	 * The command manager for this binding manager. This manager is only needed
	 * for the <code>getActiveBindingsFor(String)</code> method. This value is
	 * guaranteed to never be <code>null</code>.
	 */
	private final CommandManager commandManager;
	/**
	 * The context manager for this binding manager. For a binding manager to
	 * function, it needs to listen for changes to the contexts. This value is
	 * guaranteed to never be <code>null</code>.
	 */
	private final ContextManager contextManager;
	/**
	 * The locale for this manager. This defaults to the current locale. The
	 * value will never be <code>null</code>.
	 */
	private String locale = Locale.getDefault().toString();
	/**
	 * The array of locales, starting with the active locale and moving up
	 * through less specific representations of the locale. For example,
	 * ["en_US", "en", "", null]. This value will never be <code>null</code>.
	 */
	private String[] locales = expand(locale, LOCALE_SEPARATOR);
	/**