Don't append buckets of zero length

lib/net.js

@@ -249,20 +249,22 @@ Object.defineProperty(Stream.prototype, 'readyState', {
 
 
 Stream.prototype._appendBucket = function (data, encoding, fd) {
-  // TODO reject empty data.
-  var newBucket =  { data: data };
-  if (encoding) newBucket.encoding = encoding;
-  if (fd) newBucket.fd = fd;
+  if (data.length != 0) {
+    // TODO reject empty data.
+    var newBucket =  { data: data };
+    if (encoding) newBucket.encoding = encoding;
+    if (fd) newBucket.fd = fd;
 
-  // TODO properly calculate queueSize
+    // TODO properly calculate queueSize
 
-  if (this._writeWatcher.lastBucket) {
-    this._writeWatcher.lastBucket.next = newBucket;
-  } else {
-    this._writeWatcher.firstBucket = newBucket;
-  }
+    if (this._writeWatcher.lastBucket) {
+      this._writeWatcher.lastBucket.next = newBucket;
+    } else {
+      this._writeWatcher.firstBucket = newBucket;
+    }
 
-  this._writeWatcher.lastBucket = newBucket;
+    this._writeWatcher.lastBucket = newBucket;
+  }
 
   if (this._writeWatcher.queueSize === undefined) {
     this._writeWatcher.queueSize = 0;