code: public static int indexOfIgnoreCase(
        CharSequence sequence, CharSequence subSequence, int fromIndex) {
      return indexOfIgnoreCase(sequence, 0, sequence.length(),
          subSequence, 0, subSequence.length(), fromIndex);
    }
docs: Returns the index within the {@code sequence} of the first occurrence of {@code subSequence},
  starting at {@code fromIndex}, ignoring the case of any ASCII alphabetic characters
  between {@code 'a'} and {@code 'z'} or {@code 'A'} and {@code 'Z'} inclusive.
  
  @param sequence    the sequence to be searched in.
  @param subSequence the subsequence to search for.
  @param fromIndex   the index from which to start the search.
  @return the index of the first occurrence of the {@code subSequence}, or {@code -1} if there is
  no such occurrence.
  @since NEXT