Add list of local_addresses for network stats object

local_addresses is a list of IPs that were used to send data, which was
used during stats calculation.

Bug: webrtc:11756
Change-Id: Ie6307eaa69c73ebe9f69e44503752151be9e9ef6
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/179841
Commit-Queue: Tommi <tommi@webrtc.org>
Reviewed-by: Tommi <tommi@webrtc.org>
Reviewed-by: Andrey Logvin <landrey@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31774}

api/test/network_emulation/network_emulation_interfaces.h

@@ -11,6 +11,7 @@
 #define API_TEST_NETWORK_EMULATION_NETWORK_EMULATION_INTERFACES_H_
 
 #include <map>
+#include <vector>
 
 #include "absl/types/optional.h"
 #include "api/units/data_rate.h"
@@ -93,6 +94,10 @@ struct EmulatedNetworkStats {
   Timestamp first_packet_sent_time = Timestamp::PlusInfinity();
   Timestamp last_packet_sent_time = Timestamp::MinusInfinity();
 
+  // List of IP addresses that were used to send data considered in this stats
+  // object.
+  std::vector<rtc::IPAddress> local_addresses;
+
   std::map<rtc::IPAddress, EmulatedNetworkIncomingStats>
       incoming_stats_per_source;