Drop calls to Trace::CreateTrace and Trace::ReturnTrace from Call.

webrtc/call/call.cc

Index: webrtc/call/call.cc
diff --git a/webrtc/call/call.cc b/webrtc/call/call.cc
index ff5ebca0e205d557b32bcc61dce5dfd92c8973c9..20eddf8490f8e1e953c95d44df6791af44bb5341 100644
--- a/webrtc/call/call.cc
+++ b/webrtc/call/call.cc
@@ -52,7 +52,6 @@
 #include "webrtc/system_wrappers/include/cpu_info.h"
 #include "webrtc/system_wrappers/include/metrics.h"
 #include "webrtc/system_wrappers/include/rw_lock_wrapper.h"
-#include "webrtc/system_wrappers/include/trace.h"
 #include "webrtc/video/call_stats.h"
 #include "webrtc/video/send_delay_stats.h"
 #include "webrtc/video/stats_counter.h"
@@ -424,7 +423,6 @@ Call::Call(const Call::Config& config,
     RTC_DCHECK_GE(config.bitrate_config.max_bitrate_bps,
                   config.bitrate_config.start_bitrate_bps);
   }
-  Trace::CreateTrace();
   transport_send->send_side_cc()->RegisterNetworkObserver(this);
   transport_send_ = std::move(transport_send);
   transport_send_->send_side_cc()->SignalNetworkState(kNetworkDown);
@@ -485,8 +483,6 @@ Call::~Call() {
   }
   UpdateReceiveHistograms();
   UpdateHistograms();
-
-  Trace::ReturnTrace();
 }
 
 rtc::Optional<RtpPacketReceived> Call::ParseRtpPacket(