This reverts commit 6ff7e9ebad.
Reason for revert: <INSERT REASONING HERE>
Original change's description:
> [vmservice] allow fallback on port bind failure
>
> Work towards https://github.com/flutter/flutter/issues/46724
>
> Background:
>
> on the latest versions of iOS today, we have to use mdns to discover the observatory port and authentication code. For a variety of reasons this can fail, leaving us with no way to connect.
>
> An alternative approach is to specify the observatory port and disable the authentication code. If binding to this port fails, however, we would still like to attempt connecting with mdns.
>
> Overview:
>
> This adds a new flag to the dart SDK, --enable-service-port-fallback. This amends the behavior of the vmservice with a specified port. After failing to bind once to a non-zero port, update the port selection to 0.
>
> Results:
>
> Tested locally two dart VMs with the same specified port:
>
> ```
> jonahwilliams@jonahwilliams0:~/Documents/engine/src/out/host_debug_unopt$ ./dart --enable-service-port-fallback --observe=8080 example.dart
> Observatory server failed to start after 1 tries
> Falling back to automatic port selection
> vm-service: isolate(2785434094928835) 'main' has no debugger attached and is paused at exit. Connect to Observatory to debug.
> Observatory listening on http://127.0.0.1:45663/62A5IHjmv9E=/
> ```
>
> Change-Id: I371583edcb603325428f1cb760992e39b9f3b6dc
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/130441
> Commit-Queue: Jonah Williams <jonahwilliams@google.com>
> Reviewed-by: Ben Konyi <bkonyi@google.com>
TBR=bkonyi@google.com,jonahwilliams@google.com
Change-Id: I337b2d549e33ef9c616c276a48ce894a14b1c317
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/133327
Reviewed-by: Jonah Williams <jonahwilliams@google.com>
Commit-Queue: Jonah Williams <jonahwilliams@google.com>
cdeb9a7a8c