Breaking change request: https://dartbug.com/52334
Four abstract pure-interface classes in `stream.dart` have
been missed, and not made into `interface` declarations
like other similar abstract interface-only classes.
They should be marked `interface`, for consistency,
and to express intent.
The classes are:
* `StreamConsumer`
* `StreamIterator`
* `StreamTransformer`
* `MultiStreamController`
All are abstract classes with only abstract instance members.
Only `StreamConsumer` has uses where it is extended.
Most of those are inside the SDK, and are fixed here.
Two more are in packages (`http_server` and `streams`).
The former is discontinued and archived, and will never have a 3.0
release. The latter is internally developed and easy to fix.
Hope to cherry pick this for 3.0.3
Tested: Modified affected tests. Only adding restrictions.
CoreLibraryReviewExempt: Adding modifiers only.
Change-Id: I41aa47e48eaf769b7bd9d3206c1079a16ef3d476
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/302204
Reviewed-by: Nate Bosch <nbosch@google.com>
Commit-Queue: Lasse Nielsen <lrn@google.com>
Lasse R.H. Nielsen
7e56658645