reserve method
Resize array
if needed to have at least size
bytes free */
Implementation
void reserve(int size) {
if (length + size <= array.length) {
return;
}
var l = array.length;
while (length + size > l) {
l = (l * 1.5).ceil();
}
var newArray = Uint8List.fromList(array);
array = newArray;
}