Sets the two bytes starting at the specified
byteOffset in this
object to the two's complement binary representation of the specified
value, which must fit in two bytes.
In other words,
value must lie
between -215 and 215 - 1, inclusive.
Throws RangeError if
byteOffset is negative, or
byteOffset + 2 is greater than the length of this object.
void setInt16(int byteOffset, int value, [Endianness endian = Endianness.BIG_ENDIAN]);