Remote debugging fails due to incorrect path mappings #5075

Environment data

• VS Code version: 1.32.3
• Extension version (available under the Extensions sidebar): 2019.3.6215
• OS and version: Windows_NT x64 10.0.16299, Ubuntu 18.04
• Python version (& distribution if applicable, e.g. Anaconda): 3.6.7
• Type of virtual environment used (N/A | venv | virtualenv | conda | ...): venv

Expected behaviour

Pydev should be able to resolve the paths fine and start debugging

Actual behaviour

pydev debugger: warning: trying to add breakpoint to file that does not exist: /mnt/c/Users/limxuan/Desktop/PYTHON Entity Graph Webapp/Dependency_Grapher/C:/Users/limxuan/Desktop/PYTHON Entity Graph Webapp/Dependency_Grapher/graph_handler.py (will have no effect)

Steps to reproduce:

1. Have this in your launch.json:

    {
        "name": "Python: Remote Attach",
        "type": "python",
        "request": "attach",
        "port": 5678,
        "host": "127.0.0.1",
        "pathMappings": [
            {
                "localRoot": "${workspaceFolder}",
                "remoteRoot": "."
            }
        ]
    }
   

Logs

Nothing exciting, so I won't post it

Apologies if there are duplicates, didn't catch any when I ran this