Piping audio interruption metrics to API layer

Bug: webrtc:10549
Change-Id: Ie6abe5819c5b73dc5f5f89bdc375bad77f44ce97
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/134303
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Ivo Creusen <ivoc@webrtc.org>
Commit-Queue: Henrik Lundin <henrik.lundin@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27788}

modules/audio_coding/include/audio_coding_module_typedefs.h

@@ -130,6 +130,10 @@ struct NetworkStatistics {
   uint64_t delayedPacketOutageSamples;
   // arrival delay of incoming packets
   uint64_t relativePacketArrivalDelayMs;
+  // number of audio interruptions
+  int32_t interruptionCount;
+  // total duration of audio interruptions
+  int32_t totalInterruptionDurationMs;
 };
 
 }  // namespace webrtc