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/CommandEvent.java
throw new NullPointerException();
		this.command = command;
		if (categoryChanged) {
			changedValues |= CHANGED_CATEGORY;
		}
		if (handledChanged) {
			changedValues |= CHANGED_HANDLED;
		}
		if (parametersChanged) {
			changedValues |= CHANGED_PARAMETERS;
		}
		if (returnTypeChanged) {
			changedValues |= CHANGED_RETURN_TYPE;
		}
	}
	/**
	 * Returns the instance of the interface that changed.
	 * 
	 * @return the instance of the interface that changed. Guaranteed not to be
	 *         <code>null</code>.
	 */
	public final Command getCommand() {
		return command;
	}
	/**
	 * Returns whether or not the category property changed.
	 * 
	 * @return <code>true</code>, iff the category property changed.
	 */
	public final boolean isCategoryChanged() {