This reverts commit 4981cbffe2.
Reason for revert: Mac regression test failed.
Original change's description:
> [ VM Service / DDS ] Add custom service stream support
>
> Setting the `stream` parameter on `developer.postEvent` will now forward those events to a custom stream inside DDS.
>
>
> The first use of this will be for widget inspection. A navigation event will be posted to a custom stream. Our IDE DAP can listen for the Event and react to it by navigating to the desired location in the code.
>
> TEST=Updated observatory tests. Created new developer test to check assertions. Added DDS tests for new custom stream behaviour. Manually tested the postEvent and StreamListen with multiple clients
>
> https://github.com/flutter/devtools/issues/4533
>
> Change-Id: I870dc634c9a9a7d2ee3a6605319c2a18517ad197
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/274061
> Reviewed-by: Ben Konyi <bkonyi@google.com>
> Commit-Queue: Dan Chevalier <danchevalier@google.com>
TBR=bkonyi@google.com,dart-scoped@luci-project-accounts.iam.gserviceaccount.com,danchevalier@google.com
Change-Id: Ia1dce25444a6329c0553c931c9a6dbbec65ee583
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/274802
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Dan Chevalier <danchevalier@google.com>
3ed65601b0