Added broadcasting feature to UDP server sockets.

net/udp/udp_socket_libevent.h

Index: net/udp/udp_socket_libevent.h
diff --git a/net/udp/udp_socket_libevent.h b/net/udp/udp_socket_libevent.h
index 2101abb8c89349f5812013e8f9380b96a5981d01..842dce403e773e25ccef64b21138577e8d8bdce3 100644
--- a/net/udp/udp_socket_libevent.h
+++ b/net/udp/udp_socket_libevent.h
@@ -104,6 +104,8 @@ class NET_EXPORT UDPSocketLibevent : public base::NonThreadSafe {
 
   const BoundNetLog& NetLog() const { return net_log_; }
 
+  void AllowBroadcast();
+
  private:
   static const int kInvalidSocket = -1;
 
@@ -173,10 +175,12 @@ class NET_EXPORT UDPSocketLibevent : public base::NonThreadSafe {
   int InternalRecvFrom(IOBuffer* buf, int buf_len, IPEndPoint* address);
   int InternalSendTo(IOBuffer* buf, int buf_len, const IPEndPoint* address);
 
+  int DoBroadcast();
   int DoBind(const IPEndPoint& address);
   int RandomBind(const IPEndPoint& address);
 
   int socket_;
+  bool allow_broadcast_;
 
   // How to do source port binding, used only when UDPSocket is part of
   // UDPClientSocket, since UDPServerSocket provides Bind.