Run container with non-existent network error not consistent in swarm mode

[chris-crone]

Description

Running a container with a network that doesn't exist gives a different error message when the daemon is in swarm mode.

Steps to reproduce the issue:

1. Try to run container and check error: docker run --rm --network=does-not-exist alpine
2. Enable swarm: docker swarm init
3. Retry running container and see that error has changed: docker run --rm --network=does-not-exist alpine

Describe the results you received:

> docker run --rm --network=does-not-exist alpine
docker: Error response from daemon: No such network: does-not-exist.
> docker swarm init
...
> docker run --rm --network=does-not-exist alpine
docker: Error response from daemon: Could not attach to network does-not-exist: rpc error: code = NotFound desc = network does-not-exist not found.

Describe the results you expected:

Same error with and without swarm enabled.

Additional information you deem important (e.g. issue happens only occasionally):

Output of docker version:

Client:
 Version:      17.09.0-ce-rc1
 API version:  1.31
 Go version:   go1.8.3
 Git commit:   ae21824
 Built:        Wed Sep  6 22:25:36 2017
 OS/Arch:      darwin/amd64

Server:
 Version:      17.09.0-ce-rc1
 API version:  1.32 (minimum version 1.12)
 Go version:   go1.8.3
 Git commit:   ae21824
 Built:        Wed Sep  6 22:31:19 2017
 OS/Arch:      linux/amd64
 Experimental: true

Output of docker info:

Containers: 0
 Running: 0
 Paused: 0
 Stopped: 0
Images: 136
Server Version: 17.09.0-ce-rc1
Storage Driver: overlay2
 Backing Filesystem: extfs
 Supports d_type: true
 Native Overlay Diff: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
 Volume: local
 Network: bridge host ipvlan macvlan null overlay
 Log: awslogs fluentd gcplogs gelf journald json-file logentries splunk syslog
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 06b9cb35161009dcb7123345749fef02f7cea8e0
runc version: 3f2f8b84a77f73d38244dd690525642a72156c64
init version: 949e6fa
Security Options:
 seccomp
  Profile: default
Kernel Version: 4.9.46-moby
Operating System: Alpine Linux v3.5
OSType: linux
Architecture: x86_64
CPUs: 6
Total Memory: 7.786GiB
Name: moby
ID: WC7P:XKCN:EHGX:DM2B:B3IC:GUP4:CJY5:L3LP:UTIQ:R4HR:DOLO:UDIO
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): true
 File Descriptors: 19
 Goroutines: 38
 System Time: 2017-09-18T12:10:51.550428795Z
 EventsListeners: 1
No Proxy: *.local, 169.254/16
Registry: https://index.docker.io/v1/
Experimental: true
Insecure Registries:
 127.0.0.0/8
Live Restore Enabled: false

Additional environment details (AWS, VirtualBox, physical, etc.):
Found containerizing integration tests: #34805