Fix bug in ByteArray.subByteArray implementation for omitted length.

lib/scalarlist/byte_arrays.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * A random-access sequence of bytes that also provides random access to
  * the fixed-width integers and floating point numbers represented by
  * those bytes. Byte arrays may be used to pack and unpack data from
  * external sources (such as networks or files systems), and to process
  * large quantities of numerical data more efficiently than would be possible
@@ skipping 15 matching lines @@
   int lengthInBytes();
 
   /**
    * Returns a [ByteArray] _view_ of a portion of this byte array.
    * The returned byte array consists of [length] bytes starting
    * at position [start] in this byte array. The returned byte array
    * is backed by the same data as this byte array. In other words,
    * changes to the returned byte array are visible in this byte array
    * and vice-versa.
    *
-   * Throws [IndexOutOfRangeException] if [start] is negative, or if
-   * `start + length` is greater than the length of this byte array.
+   * Throws [IndexOutOfRangeException] if [start] or [length] are negative, or
+   * if `start + length` is greater than the length of this byte array.
    *
    * Throws [ArgumentError] if [length] is negative.
    */
   ByteArray subByteArray([int start, int length]);
 
   /**
    * Returns the (possibly negative) integer represented by the byte at the
    * specified [byteOffset] in this byte array, in two's complement binary
    * representation. The return value will be between -128 and 127, inclusive.
    *
@@ skipping 613 matching lines @@
    * [start] of the region is not divisible by 8. If, however, [array]
    * is a view of another byte array, this constructor will throw
    * [ArgumentError] if the implicit starting position in the
    * "ultimately backing" byte array is not divisible by 8. In plain terms,
    * this constructor throws [ArgumentError] if the specified
    * region does not contain an integral number of "float64s," or if it
    * is not "float64-aligned."
    */
   external factory Float64List.view(ByteArray array, [int start, int length]);
 }