Fixes #355 by adding test for windows device path;

Author: Lingjia

lib/util.js

@@ -225,7 +225,7 @@ function join(aRoot, aPath) {
     return urlGenerate(aRootUrl);
   }
 
-  const joined = aPath.charAt(0) === "/"
+  const joined = exports.isAbsolute(aPath.charAt(0))
     ? aPath
     : normalize(aRoot.replace(/\/+$/, "") + "/" + aPath);
 
@@ -238,7 +238,9 @@ function join(aRoot, aPath) {
 exports.join = join;
 
 exports.isAbsolute = function(aPath) {
-  return aPath.charAt(0) === "/" || urlRegexp.test(aPath);
+  return aPath[0] === "/" ||
+      (aPath[1] === ":" && (aPath[2] === "\\" || aPath[2] === "/")) ||
+      urlRegexp.test(aPath);
 };
 
 /**