VSCode variables ${workspaceFolder} and ${workspaceRoot} are not populated

[dfluff]

I'm trying to use SSHFS along with the PHP Debug plugin. The latter requires that you make path mappings between the PHP remote server and the local workspace, like:

"pathMappings": {
    "file:///var/www/html/myfiles/": "${workspaceRoot}/"
}

However, this is not working, and I believe the reason is that when you have an SSHFS workspace open the VSCode internal variable ${workspaceRoot} is not being populated. I believe the same is true for ${workspaceFolder}.

[SchoofsKelvin]

Related to #142.

This seems more like an issue with how VSCode resolves these variables. Maybe #142 might help with that once (but only if) it gets implemented.