Expected behavior

Docker upgrade shouldn't affect already working mount mappings.

Actual behavior

Upgrade to new version of docker on Mac OSX now results in "The path /etc/localtime
is not shared from OS X and is not known to Docker".

Information

• Full output of the diagnostics from "Diagnose & Feedback" in the menu

Docker for Mac: version: 17.12.0-ce-mac46 (a61e84b8bca06b1ae6ce058cdd7beab1520ad622)
macOS: version 10.12.6 (build: 16G1114)
logs: /tmp/072847D3-A6CD-4D63-BC1A-BE8199F81553/20180110-104443.tar.gz
[OK] db.git
[OK] vmnetd
[OK] dns
[OK] driver.amd64-linux
[OK] virtualization VT-X
[OK] app
[OK] moby
[OK] system
[OK] moby-syslog
[OK] kubernetes
[OK] env
[OK] virtualization kern.hv_support
[OK] slirp
[OK] osxfs
[OK] moby-console
[OK] logs
[OK] docker-cli
[OK] menubar
[OK] disk

• A reproducible case if this is a bug, Dockerfiles FTW
• Page URL if this is a docs issue or the name of a man page

Steps to reproduce the behavior

1.On previous version, Existing docker run command executed successfully as:

docker run -d -p 80 \
    --name ${CONTAINER_NAME} \
    --restart=always \
    -v /etc/localtime:/etc/localtime:ro \
    -v ${ENV_APPDIR}/app:/usr/share/app:ro \
    -l agent-host=${agent_host} \
    ${CONTAINER_NAME}

2. Upgrade to new Docker release
3. Same docker run command now fails with

docker: Error response from daemon: Mounts denied:
The path /etc/localtime
is not shared from OS X and is not known to Docker.
You can configure shared paths from Docker -> Preferences... -> File Sharing.
See https://docs.docker.com/docker-for-mac/osxfs/#namespaces for more info.