Fix style; undefined reference bug

lib/fs.js

@@ -611,6 +611,8 @@ fs.createReadStream = function(path, options) {
 var ReadStream = fs.ReadStream = function(path, options) {
   events.EventEmitter.call(this);
 
+  var self = this;
+
   this.path = path;
   this.fd = null;
   this.readable = true;
@@ -629,11 +631,12 @@ var ReadStream = fs.ReadStream = function(path, options) {
     this[key] = options[key];
   }
 
-  if(this.start || this.end) {
-    if(this.start === undefined || this.end === undefined) {
-      self.emit('error', new Error('Both start and end are needed for range streaming.'));
-    } else if(this.start > this.end) {
-      self.emit('error', new Error('start must be <= end'));
+  if (this.start || this.end) {
+    if (this.start === undefined || this.end === undefined) {
+      this.emit('error',
+        new Error('Both start and end are needed for range streaming.'));
+    } else if (this.start > this.end) {
+      this.emit('error', new Error('start must be <= end'));
     } else {
       this.firstRead = true;
     }
@@ -643,7 +646,6 @@ var ReadStream = fs.ReadStream = function(path, options) {
     return;
   }
 
-  var self = this;
   fs.open(this.path, this.flags, this.mode, function(err, fd) {
     if (err) {
       self.emit('error', err);