private static void appendFunctionSignature(
     final StringBuilder builder, final DartComponent function, final String returnType) {
   builder.append("<b>").append(function.getName()).append("</b>");
   if (!function.isGetter()) {
     builder.append('(');
     builder.append(
         StringUtil.escapeXml(
             DartPresentableUtil.getPresentableParameterList(
                 function, new DartGenericSpecialization(), true, true)));
     builder.append(')');
   }
   builder.append(' ');
   builder.append(DartPresentableUtil.RIGHT_ARROW);
   builder.append(' ');
   builder.append(returnType);
 }