Correctly return from Stream.write()

In some cases, the attempt to flush the writeQueue might be successful,
meaning that the queueSize is in fact 0, but the captured size *prior*
to the flush was large enough to return false.

Read the current queueSize when deciding to return false from write().

lib/net.js

@@ -285,7 +285,7 @@ Stream.prototype.write = function (data, encoding, fd) {
     IOWatcher.flush();
   }
 
-  return queueSize < (64*1024);
+  return this._writeWatcher.queueSize > (64*1024);
 };