Naive fix for "Cannot call method 'charAt' of undefined" in Less.css

parser.js

    function getInput(e, env) {
        if (e.filename && env.filename && (e.filename !== env.filename)) {
			var baseFilename = basename(e.filename);
			for (f in parser.imports.contents) {
				if (parser.imports.contents.hasOwnProperty(f) && f.indexOf(baseFilename) >= 0) {
					return parser.imports.contents[f];
				}
			}
            return parser.imports.contents[baseFilename];
        } else {
            return input;
        }
    }