Pepper: Allow plugins to call PPB_UDP_Socket::SendTo multiple times.

ppapi/cpp/udp_socket.h

 // Copyright 2013 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 PPAPI_CPP_UDP_SOCKET_H_
 #define PPAPI_CPP_UDP_SOCKET_H_
 
 #include "ppapi/c/ppb_udp_socket.h"
 #include "ppapi/cpp/net_address.h"
 #include "ppapi/cpp/pass_ref.h"
@@ skipping 107 matching lines @@
   /// @param[in] num_bytes The number of bytes to send.
   /// @param[in] addr A <code>NetAddress</code> object holding the destination
   /// address.
   /// @param[in] callback A <code>CompletionCallback</code> to be called upon
   /// completion.
   ///
   /// @return A non-negative number on success to indicate how many bytes have
   /// been sent; otherwise, an error code from <code>pp_errors.h</code>.
   /// <code>PP_ERROR_NOACCESS</code> will be returned if the caller doesn't have
   /// required permissions.
+  /// <code>PP_ERROR_INPROGRESS</code> will be returned if the socket is busy
+  /// sending. The caller should wait until a pending send completes before
+  /// retrying.
   int32_t SendTo(const char* buffer,
                  int32_t num_bytes,
                  const NetAddress& addr,
                  const CompletionCallback& callback);
 
   /// Cancels all pending reads and writes, and closes the socket. Any pending
   /// callbacks will still run, reporting <code>PP_ERROR_ABORTED</code> if
   /// pending IO was interrupted. After a call to this method, no output
   /// paramters passed into previous <code>RecvFrom()</code> calls will be
   /// accessed. It is not valid to call <code>Bind()</code> again.
@@ skipping 13 matching lines @@
   ///
   /// @return An int32_t containing an error code from <code>pp_errors.h</code>.
   int32_t SetOption(PP_UDPSocket_Option name,
                     const Var& value,
                     const CompletionCallback& callback);
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_UDP_SOCKET_H_