Bug 126414 [Commands] handlers: Provide help context ids
For commands and handlers to replace actions, they need to be capable of providing help context identifiers. For an example, see OpenResourceHandler in org.eclipse.ui.ide. This help context id will need to be definable through XML and through code.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/CommandManager.java
/**
	 * {@inheritDoc}
	 * 
	 * @since 3.2
	 */
	public final void parameterTypeChanged(
			final ParameterTypeEvent parameterTypeEvent) {
		if (parameterTypeEvent.isDefinedChanged()) {
			final ParameterType parameterType = parameterTypeEvent
					.getParameterType();
			final String parameterTypeId = parameterType.getId();
			final boolean parameterTypeIdAdded = parameterType.isDefined();
			if (parameterTypeIdAdded) {
				definedParameterTypeIds.add(parameterTypeId);
			} else {
				definedParameterTypeIds.remove(parameterTypeId);
			}
			fireCommandManagerChanged(new CommandManagerEvent(this,
					parameterTypeId, parameterTypeIdAdded, true));
		}
	}
	/**
	 * Removes a listener from this command manager.
	 * 
	 * @param listener
	 *            The listener to be removed; must not be <code>null</code>.
	 */
	public final void removeCommandManagerListener(
			final ICommandManagerListener listener) {
		removeListenerObject(listener);