static rangeCheck(arrayLength, fromIndex, toIndex) {
			if (fromIndex > toIndex) {
				throw new IllegalArgumentException('fromIndex(' + fromIndex + ') > toIndex(' + toIndex + ')');
			}
			if (fromIndex < 0) {
				throw new ArrayIndexOutOfBoundsException(fromIndex);
			}
			if (toIndex > arrayLength) {
				throw new ArrayIndexOutOfBoundsException(toIndex);
			}
		}
Checks that {@code fromIndex} and {@code toIndex} are in
the range and throws an exception if they aren't.