Add Socket::ReadIfReady()

net/socket/socket.cc

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/socket/socket.h"
+
+#include "net/base/net_errors.h"
+
+namespace net {
+
+const base::Feature Socket::kReadIfReadyExperiment{
+    "SocketReadIfReady", base::FEATURE_DISABLED_BY_DEFAULT};
+
+int Socket::ReadIfReady(IOBuffer* buf,
+                        int buf_len,
+                        const CompletionCallback& callback) {
+  return ERR_READ_IF_READY_NOT_IMPLEMENTED;
+}
+
+}  // namespace net