fix for failed download with no subtitles when requested

this should do it ...

lib/youtube-dl.js

@@ -18,25 +18,11 @@ fs.exists(file, function(exists) {
 
 var isYouTubeRegex = /^(https?:\/\/)?(www\.)?(youtube\.com|youtu\.be)\//;
 var isNoSubsRegex = /WARNING: video doesn't have subtitles/;
-var subs = ['--write-sub', '--write-srt', '--srt-lang', '--all-subs'];
+var subsRegex = /--write-sub|--write-srt|--srt-lang|--all-subs/;
 
 // Check if win.
 var isWin = /^win/.test(process.platform);
 
-/**
- * Regular Expresion IndexOf for Arrays
- *
- * @param {Array.<String>} arr
- * @param {String} rx
- */
-function reIndexOf(arr, rx) {
- var i;
- for (i = arr.length - 1; i >= 0; i--) {
- if (arr[i].toString().match(rx)) { return i; }
- }
- return -1;
-}
-
 /**
  * Downloads a video.
  *
@@ -121,12 +107,13 @@ function call(video, args1, args2, options, callback) {
 
  // Try once to download video if no subtitles available
  if (!options.nosubs && isNoSubsRegex.test(stderr)) {
+
+ var i;
  var cleanupOpt = opt[1];
 
- subs.map(function map(item) {
- var target = reIndexOf(cleanupOpt, item);
- if (target > -1) { cleanupOpt.splice(target, 1); }
- });
+ for (i = cleanupOpt.length - 1; i >= 0; i--) {
+ if (subsRegex.test(cleanupOpt[i])) { cleanupOpt.splice(i, 1); }
+ }
 
  options.nosubs = true;