code: public boolean contains(CharSequence name, CharSequence value, boolean ignoreCase) {
          return contains(name.toString(), value.toString(), ignoreCase);
      }
docs: Returns {@code true} if a header with the {@code name} and {@code value} exists, {@code false} otherwise.
  <p>
  If {@code ignoreCase} is {@code true} then a case insensitive compare is done on the value.
  @param name the name of the header to find
  @param value the value of the header to find
  @param ignoreCase {@code true} then a case insensitive compare is run to compare values.
  otherwise a case sensitive compare is run to compare values.