Fix cut/paste error in MEDIA_CODEC_REPORTED

cut&paste error in the MEDIA_CODEC_REPORTED was emitting
codec name where it should have emitted log-session-id

Bug: 228327181
Test: examine emitted statsd atoms
Change-Id: Ieb9cd700fa8df127a87e06b9a68abebf6888d050
diff --git a/services/mediametrics/statsd_codec.cpp b/services/mediametrics/statsd_codec.cpp
index 17a3a5f..e322d62 100644
--- a/services/mediametrics/statsd_codec.cpp
+++ b/services/mediametrics/statsd_codec.cpp
@@ -231,7 +231,7 @@
         sessionId = mediametrics::ValidateId::get()->validateId(sessionId);
         metrics_proto.set_log_session_id(sessionId);
     }
-    AStatsEvent_writeString(event, codec.c_str());
+    AStatsEvent_writeString(event, sessionId.c_str());
 
     int32_t channelCount = -1;
     if (item->getInt32("android.media.mediacodec.channelCount", &channelCount)) {