http: make OutgoingMessage._flush inline-able

lib/_http_outgoing.js

@@ -525,7 +525,6 @@ OutgoingMessage.prototype._finish = function() {
 };
 
 
-OutgoingMessage.prototype._flush = function() {
 // This logic is probably a bit confusing. Let me explain a bit:
 //
 // In both HTTP servers and clients it is possible to queue up several
@@ -545,18 +544,13 @@ OutgoingMessage.prototype._flush = function() {
 //
 // This function, outgoingFlush(), is called by both the Server and Client
 // to attempt to flush any pending messages out to the socket.
-
-  if (!this.socket) return;
-
+OutgoingMessage.prototype._flush = function() {
+  if (this.socket && this.socket.writable) {
     var ret;
     while (this.output.length) {
-
-    if (!this.socket.writable) return; // XXX Necessary?
-
       var data = this.output.shift();
       var encoding = this.outputEncodings.shift();
       var cb = this.outputCallbacks.shift();
-
       ret = this.socket.write(data, encoding, cb);
     }
 
@@ -567,4 +561,5 @@ OutgoingMessage.prototype._flush = function() {
       // This is necessary to prevent https from breaking
       this.emit('drain');
     }
+  }
 };