docker images --digest image does not display digest

Description

The image digest is <none> if you specify the image.

Steps to reproduce the issue:

C:\Users\camer\tmp> docker images --digests
REPOSITORY          TAG                 DIGEST                                                                    IMAGE ID            CREATED             SIZE
mono                latest              sha256:55ce025f24578afe68cdf579dd3a42b9af7e4c729eadefa1f0a236d6387a8eb2   61351f52f2f9        3 weeks ago         531MB
mono                slim                sha256:9cb9c6131656a1ea0413e22fa5854a38672d792e63be3fd51c4da214b43113ae   ac8dc438b799        3 weeks ago         170MB
C:\Users\camer\tmp> docker images --digests mono:slim
REPOSITORY          TAG                 DIGEST              IMAGE ID            CREATED             SIZE
mono                slim                <none>              ac8dc438b799        3 weeks ago         170MB

Describe the results you received:

Describe the results you expected:
I want the digest displayed.

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

Output of docker version:

C:\Users\camer\tmp> docker --version
Docker version 17.09.0-ce, build afdb6d4

Output of docker info:

C:\Users\camer\tmp> docker info
Containers: 0
 Running: 0
 Paused: 0
 Stopped: 0
Images: 2
Server Version: 17.09.0-ce
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: 4.9.49-moby
Operating System: Alpine Linux v3.5
OSType: linux
Architecture: x86_64
CPUs: 2
Total Memory: 1.934GiB
Name: moby
ID: XEH3:K2GT:SI6C:LDQH:CCLI:46Y2:IISU:RXUS:56QI:GLQJ:25TP:DCXF
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): true
 File Descriptors: 16
 Goroutines: 26
 System Time: 2017-12-04T22:02:36.4444744Z
 EventsListeners: 0
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.):

Looks related to https://github.com/docker/cli/pull/439

Reproduce the issue with docker images --digests and a specific image tag, then trace the Docker CLI code for image listing and digest formatting. Done means the tagged-image form displays the same digest as the unfiltered listing, with coverage for the reported case.