Edit Color Scheme does not work if the color_scheme setting has no path

[OdatNurd]

The PackageDev: Edit Current Color Scheme command generates an error dialog if your color_scheme preference is set just to the name of a color scheme file instead of a full resource file path.

Looking in PackageDev/plugins_/color_scheme_dev.py, the reason seems to be that the command creates a ResourcePath() based on the value of the setting, and then tries to use it to come up with the appropriate paths. However when the setting doesn't contain a path, this ends up with a filename that's not valid:

        scheme_path = ResourcePath(view.settings().get('color_scheme'))
        self.window.run_command(
            'edit_settings',
            {
                "base_file": '/'.join(("${packages}",) + scheme_path.parts[1:]),
                "user_file": "${packages}/User/" + scheme_path.stem + '.sublime-color-scheme',
                "default": SCHEME_TEMPLATE,
            },
        )

In order for the command to work you need to edit the color scheme preference to include a full package resource spec or use UI: Select Color Scheme to modify the color_scheme setting for you, since that command always uses a full resource filename when it modifies the setting.