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

net/udp/udp_server_socket.cc

Index: net/udp/udp_server_socket.cc
diff --git a/net/udp/udp_server_socket.cc b/net/udp/udp_server_socket.cc
index ad19655aa54b23bd3aca82ad7f2d856f15790bc4..796c04da503bcda479c1822d68ce9e53173ee617 100644
--- a/net/udp/udp_server_socket.cc
+++ b/net/udp/udp_server_socket.cc
@@ -37,11 +37,11 @@ int UDPServerSocket::SendTo(IOBuffer* buf,
   return socket_.SendTo(buf, buf_len, address, callback);
 }
 
-bool UDPServerSocket::SetReceiveBufferSize(int32 size) {
+int UDPServerSocket::SetReceiveBufferSize(int32 size) {
   return socket_.SetReceiveBufferSize(size);
 }
 
-bool UDPServerSocket::SetSendBufferSize(int32 size) {
+int UDPServerSocket::SetSendBufferSize(int32 size) {
   return socket_.SetSendBufferSize(size);
 }