Use RTC_UNUSED instead of conditional compilation in BWE simulator tool.

webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.h

Index: webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.h
diff --git a/webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.h b/webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.h
index c5a16a68b8935ad9378becf041a7d4832107252a..adc3b9951d4d55918613ee08ed2c971b5834f268 100644
--- a/webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.h
+++ b/webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.h
@@ -34,6 +34,7 @@
 #include "webrtc/modules/remote_bitrate_estimator/test/packet.h"
 #include "webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h"
 #include "webrtc/system_wrappers/include/clock.h"
+#include "webrtc/typedefs.h"
 
 namespace webrtc {
 
@@ -250,9 +251,7 @@ class RateCounterFilter : public PacketProcessor {
   Stats<double> packets_per_second_stats_;
   Stats<double> kbps_stats_;
   int64_t start_plotting_time_ms_;
-#if BWE_TEST_LOGGING_COMPILE_TIME_ENABLE
   int flow_id_ = 0;
-#endif
   std::string name_;
   // Algorithm name if single flow, Total link utilization if all flows.
   std::string algorithm_name_;