Breaking change 44039: Fix HttpClient callback argument nullability

[Lasse R.H. Nielsen]

A mistake was made during migration of dart:io where some callback arguments were not made nullable, even though the function could be called with null.

See https://github.com/dart-lang/sdk/issues/44039

Fixing the mistake is breaking, but only to null-safe code, since it only changes the nullability of a single callback argument.

/L

--

Lasse R.H. Nielsen - l...@google.com  

'Faith without judgement merely degrades the spirit divine'
Google Denmark ApS - Frederiksborggade 20B, 1 sal - 1360 København K - Denmark - CVR nr. 28 86 69 84

[Lasse R.H. Nielsen]

(If you expect the change to affect your code negatively, please comment on the issue).

/L