Enable probing with repeated payload packets by default.

webrtc/modules/rtp_rtcp/source/rtp_sender.h

Index: webrtc/modules/rtp_rtcp/source/rtp_sender.h
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_sender.h b/webrtc/modules/rtp_rtcp/source/rtp_sender.h
index 6d11e8044dcbd17783ac0d166f409369c2cdf47d..43a30b282652709aa7b4f7c6ee30e18d75401b3f 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_sender.h
+++ b/webrtc/modules/rtp_rtcp/source/rtp_sender.h
@@ -297,9 +297,10 @@ class RTPSender : public RTPSenderInterface {
   int32_t SetFecParameters(const FecProtectionParams *delta_params,
                            const FecProtectionParams *key_params);
 
-  size_t SendPadData(uint32_t timestamp,
-                     int64_t capture_time_ms,
-                     size_t bytes);
+  size_t SendPadData(size_t bytes,
+                     bool timestamp_provided,
+                     uint32_t timestamp,
+                     int64_t capture_time_ms);
 
   // Called on update of RTP statistics.
   void RegisterRtpStatisticsCallback(StreamDataCountersCallback* callback);
@@ -341,9 +342,10 @@ class RTPSender : public RTPSenderInterface {
   // Return the number of bytes sent.  Note that both of these functions may
   // return a larger value that their argument.
   size_t TrySendRedundantPayloads(size_t bytes);
-  size_t TrySendPadData(size_t bytes);
 
-  size_t BuildPaddingPacket(uint8_t* packet, size_t header_length);
+  void BuildPaddingPacket(uint8_t* packet,
+                          size_t header_length,
+                          size_t padding_length);
 
   void BuildRtxPacket(uint8_t* buffer, size_t* length,
                       uint8_t* buffer_rtx);