Infection hates null coalescing

[teresko]

How I am supposed to test this ?

-        return $this->list[$key] ?? null;
+        return null ?? $this->list[$key];

[sanmai]

Could you file a bug report?

[teresko]

Wasn't a bug, the problem was genetic.

[teresko]

Nevermind.
I was being stupid.

I was looking a wrong set of unit tests and could not figure out why they were not covering it.

[maks-rafalko]

We removed this mutation in #1725, please upgrade.