code: protected Diagnostic createErrorDiagnostic(final WComponent source, final String message,
  			final Serializable... args) {
  		return new DiagnosticImpl(Diagnostic.ERROR, source, message, args);
  	}
docs: Create and return an error diagnostic associated to the given error source.
  
  @param source the source of the error.
  @param message the error message, using {@link MessageFormat} syntax.
  @param args optional arguments for the message.
  @return an error diagnostic for this component.