context ls command does not always show the default endpoints

Description
The default context shows its endpoints only if it is used as current context.
This feels like a bug once we change the current context, endpoints are missing.

$ docker context ls
NAME                DESCRIPTION                               DOCKER ENDPOINT               KUBERNETES ENDPOINT                ORCHESTRATOR
default *           Current DOCKER_HOST based configuration   unix:///var/run/docker.sock   https://localhost:6443 (default)   swarm
swarm               swarm context                             unix:///var/run/docker.sock                                      swarm
$ docker context use swarm
swarm
Current context is now "swarm"
$ docker context ls
NAME                DESCRIPTION                               DOCKER ENDPOINT               KUBERNETES ENDPOINT   ORCHESTRATOR
default             Current DOCKER_HOST based configuration
swarm *             swarm context                             unix:///var/run/docker.sock                         swarm

Describe the results you expected:
Default endpoints should always be output.

Output of docker version:

$ docker version
Client:
 Version:           19.03.0-dev
 API version:       1.39 (downgraded from 1.40)
 Go version:        go1.11.4
 Git commit:        48bd4c6de
 Built:             Wed Jan 16 17:12:16 2019
 OS/Arch:           darwin/amd64
 Experimental:      false

Server: Docker Engine - Community
 Engine:
  Version:          18.09.0
  API version:      1.39 (minimum version 1.12)
  Go version:       go1.10.4
  Git commit:       4d60db4
  Built:            Wed Nov  7 00:55:00 2018
  OS/Arch:          linux/amd64
  Experimental:     true