lib: reduce overhead of blob clone
Continuing the work started on https://github.com/nodejs/performance/issues/109
confidence improvement accuracy (*) (**) (***)
blob/clone.js bytes=1024 n=50000 *** 60.74 % ±1.58% ±2.11% ±2.75%
blob/clone.js bytes=1048576 n=50000 *** 50.70 % ±1.84% ±2.46% ±3.23%
blob/clone.js bytes=128 n=50000 *** 62.57 % ±1.43% ±1.91% ±2.49%
Be aware that when doing many comparisons the risk of a false-positive
result increases. In this case, there are 3 comparisons, you can thus
expect the following amount of false-positive results:
0.15 false positives, when considering a 5% risk acceptance (*, **, ***),
0.03 false positives, when considering a 1% risk acceptance (**, ***),
0.00 false positives, when considering a 0.1% risk acceptance (***)
/cc @nodejs/performance