Revert "[ Service / DDS ] Advertise DDS as the VM service, bump version to 4.0"

This reverts commit 0ea18ffb361300039787eebf76e89e181dca7c0a.

Reason for revert: Tree is on fire

Original change's description:
> [ Service / DDS ] Advertise DDS as the VM service, bump version to 4.0
> 
> This change does the following:
>   - The DDS URI will be reported by the VM as the VM service URI. If DDS
>     disconnects, the VM service URI will be reported instead. This only
>     impacts the standalone VM.
>   - Updated the service protocol to 4.0 and removed the following
>     deprecated functionality:
>       - Client synchronization RPCs (these now live in DDS)
>       - getWebSocketTarget (no longer needed as the VM service no longer
>         tries to redirect web socket clients to DDS)
>   - Regenerates package:vm_service based on the new spec, prepare for
>     5.0 release
> 
> Change-Id: I8a2b401062342eb99b81ef10ef6926baa88f946e
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/160141
> Reviewed-by: Siva Annamalai <asiva@google.com>

TBR=bkonyi@google.com,rmacnak@google.com,asiva@google.com

Change-Id: I6a16e9fa7ceb18555d6424a169cfa811d3833419
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/160340
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>