make SetReceiveBufferSize and SetSendBufferSize return net error codes (instead of bools)

net/socket/socket.h

 // Copyright (c) 2011 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.
 
 #ifndef NET_SOCKET_SOCKET_H_
 #define NET_SOCKET_SOCKET_H_
 
 #include "net/base/completion_callback.h"
 #include "net/base/net_export.h"
 
@@ skipping 30 matching lines @@
   // operation is not completed immediately, the socket acquires a reference to
   // the provided buffer until the callback is invoked or the socket is
   // closed.  Implementations of this method should not modify the contents
   // of the actual buffer that is written to the socket.  If the socket is
   // Disconnected before the write completes, the callback will not be invoked.
   virtual int Write(IOBuffer* buf, int buf_len,
                     const CompletionCallback& callback) = 0;
 
   // Set the receive buffer size (in bytes) for the socket.
   // Note: changing this value can affect the TCP window size on some platforms.
-  // Returns true on success, or false on failure.
-  virtual bool SetReceiveBufferSize(int32 size) = 0;
+  // Returns a net error code.
+  virtual int SetReceiveBufferSize(int32 size) = 0;
 
   // Set the send buffer size (in bytes) for the socket.
   // Note: changing this value can affect the TCP window size on some platforms.
-  // Returns true on success, or false on failure.
-  virtual bool SetSendBufferSize(int32 size) = 0;
+  // Returns a net error code.
+  virtual int SetSendBufferSize(int32 size) = 0;
 };
 
 }  // namespace net
 
 #endif  // NET_SOCKET_SOCKET_H_