diff --git a/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h b/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h
index e5065a4b56..6ed716329a 100644
--- a/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h
+++ b/webrtc/modules/audio_conference_mixer/source/audio_conference_mixer_impl.h
@@ -148,8 +148,8 @@ private:
 
     bool LimitMixedAudio(AudioFrame* mixedAudio) const;
 
-    const rtc::CriticalSection _crit;
-    const rtc::CriticalSection _cbCrit;
+    rtc::CriticalSection _crit;
+    rtc::CriticalSection _cbCrit;
 
     int32_t _id;
 
diff --git a/webrtc/modules/video_coding/media_optimization.cc b/webrtc/modules/video_coding/media_optimization.cc
index fec5c4c33b..ccd23f6ae4 100644
--- a/webrtc/modules/video_coding/media_optimization.cc
+++ b/webrtc/modules/video_coding/media_optimization.cc
@@ -33,8 +33,7 @@ struct MediaOptimization::EncodedFrameSample {
 };
 
 MediaOptimization::MediaOptimization(Clock* clock)
-    : crit_sect_(CriticalSectionWrapper::CreateCriticalSection()),
-      clock_(clock),
+    : clock_(clock),
       max_bit_rate_(0),
       codec_width_(0),
       codec_height_(0),
@@ -56,7 +55,7 @@ MediaOptimization::~MediaOptimization(void) {
 }
 
 void MediaOptimization::Reset() {
-  CriticalSectionScoped lock(crit_sect_.get());
+  rtc::CritScope lock(&crit_sect_);
   SetEncodingDataInternal(0, 0, 0, 0, 0, 0, max_payload_size_);
   memset(incoming_frame_times_, -1, sizeof(incoming_frame_times_));
   incoming_frame_rate_ = 0.0;
@@ -79,7 +78,7 @@ void MediaOptimization::SetEncodingData(int32_t max_bit_rate,
                                         uint32_t frame_rate,
                                         int num_layers,
                                         int32_t mtu) {
-  CriticalSectionScoped lock(crit_sect_.get());
+  rtc::CritScope lock(&crit_sect_);
   SetEncodingDataInternal(max_bit_rate, frame_rate, target_bitrate, width,
                           height, num_layers, mtu);
 }
@@ -107,7 +106,7 @@ void MediaOptimization::SetEncodingDataInternal(int32_t max_bit_rate,
 }
 
 uint32_t MediaOptimization::SetTargetRates(uint32_t target_bitrate) {
-  CriticalSectionScoped lock(crit_sect_.get());
+  rtc::CritScope lock(&crit_sect_);
 
   video_target_bitrate_ = target_bitrate;
 
@@ -125,7 +124,7 @@ uint32_t MediaOptimization::SetTargetRates(uint32_t target_bitrate) {
 }
 
 uint32_t MediaOptimization::InputFrameRate() {
-  CriticalSectionScoped lock(crit_sect_.get());
+  rtc::CritScope lock(&crit_sect_);
   return InputFrameRateInternal();
 }
 
@@ -137,7 +136,7 @@ uint32_t MediaOptimization::InputFrameRateInternal() {
 }
 
 uint32_t MediaOptimization::SentFrameRate() {
-  CriticalSectionScoped lock(crit_sect_.get());
+  rtc::CritScope lock(&crit_sect_);
   return SentFrameRateInternal();
 }
 
@@ -148,7 +147,7 @@ uint32_t MediaOptimization::SentFrameRateInternal() {
 }
 
 uint32_t MediaOptimization::SentBitRate() {
-  CriticalSectionScoped lock(crit_sect_.get());
+  rtc::CritScope lock(&crit_sect_);
   const int64_t now_ms = clock_->TimeInMilliseconds();
   PurgeOldFrameSamples(now_ms);
   UpdateSentBitrate(now_ms);
@@ -159,7 +158,7 @@ int32_t MediaOptimization::UpdateWithEncodedData(
     const EncodedImage& encoded_image) {
   size_t encoded_length = encoded_image._length;
   uint32_t timestamp = encoded_image._timeStamp;
-  CriticalSectionScoped lock(crit_sect_.get());
+  rtc::CritScope lock(&crit_sect_);
   const int64_t now_ms = clock_->TimeInMilliseconds();
   PurgeOldFrameSamples(now_ms);
   if (encoded_frame_samples_.size() > 0 &&
@@ -184,12 +183,12 @@ int32_t MediaOptimization::UpdateWithEncodedData(
 }
 
 void MediaOptimization::EnableFrameDropper(bool enable) {
-  CriticalSectionScoped lock(crit_sect_.get());
+  rtc::CritScope lock(&crit_sect_);
   frame_dropper_->Enable(enable);
 }
 
 bool MediaOptimization::DropFrame() {
-  CriticalSectionScoped lock(crit_sect_.get());
+  rtc::CritScope lock(&crit_sect_);
   UpdateIncomingFrameRate();
   // Leak appropriate number of bytes.
   frame_dropper_->Leak((uint32_t)(InputFrameRateInternal() + 0.5f));
diff --git a/webrtc/modules/video_coding/media_optimization.h b/webrtc/modules/video_coding/media_optimization.h
index 290636fdca..bc48300f50 100644
--- a/webrtc/modules/video_coding/media_optimization.h
+++ b/webrtc/modules/video_coding/media_optimization.h
@@ -101,7 +101,7 @@ class MediaOptimization {
   uint32_t SentFrameRateInternal() EXCLUSIVE_LOCKS_REQUIRED(crit_sect_);
 
   // Protect all members.
-  std::unique_ptr<CriticalSectionWrapper> crit_sect_;
+  rtc::CriticalSection crit_sect_;
 
   Clock* clock_ GUARDED_BY(crit_sect_);
   int32_t max_bit_rate_ GUARDED_BY(crit_sect_);
diff --git a/webrtc/modules/video_coding/receiver.cc b/webrtc/modules/video_coding/receiver.cc
index 826647c3ee..af9ddb8f26 100644
--- a/webrtc/modules/video_coding/receiver.cc
+++ b/webrtc/modules/video_coding/receiver.cc
@@ -72,8 +72,7 @@ VCMReceiver::VCMReceiver(VCMTiming* timing,
                          std::unique_ptr<EventWrapper> jitter_buffer_event,
                          NackSender* nack_sender,
                          KeyFrameRequestSender* keyframe_request_sender)
-    : crit_sect_(CriticalSectionWrapper::CreateCriticalSection()),
-      clock_(clock),
+    : clock_(clock),
       jitter_buffer_(clock_,
                      std::move(jitter_buffer_event),
                      nack_sender,
@@ -86,11 +85,10 @@ VCMReceiver::VCMReceiver(VCMTiming* timing,
 
 VCMReceiver::~VCMReceiver() {
   render_wait_event_->Set();
-  delete crit_sect_;
 }
 
 void VCMReceiver::Reset() {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   if (!jitter_buffer_.Running()) {
     jitter_buffer_.Start();
   } else {
@@ -242,7 +240,7 @@ void VCMReceiver::ReceiveStatistics(uint32_t* bitrate, uint32_t* framerate) {
 void VCMReceiver::SetNackMode(VCMNackMode nackMode,
                               int64_t low_rtt_nack_threshold_ms,
                               int64_t high_rtt_nack_threshold_ms) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   // Default to always having NACK enabled in hybrid mode.
   jitter_buffer_.SetNackMode(nackMode, low_rtt_nack_threshold_ms,
                              high_rtt_nack_threshold_ms);
@@ -256,7 +254,7 @@ void VCMReceiver::SetNackSettings(size_t max_nack_list_size,
 }
 
 VCMNackMode VCMReceiver::NackMode() const {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   return jitter_buffer_.nack_mode();
 }
 
@@ -273,7 +271,7 @@ VCMDecodeErrorMode VCMReceiver::DecodeErrorMode() const {
 }
 
 int VCMReceiver::SetMinReceiverDelay(int desired_delay_ms) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   if (desired_delay_ms < 0 || desired_delay_ms > kMaxReceiverDelayMs) {
     return -1;
   }
diff --git a/webrtc/modules/video_coding/receiver.h b/webrtc/modules/video_coding/receiver.h
index a8d3ef3a6b..0664d6247f 100644
--- a/webrtc/modules/video_coding/receiver.h
+++ b/webrtc/modules/video_coding/receiver.h
@@ -14,10 +14,10 @@
 #include <memory>
 #include <vector>
 
+#include "webrtc/base/criticalsection.h"
 #include "webrtc/modules/video_coding/jitter_buffer.h"
 #include "webrtc/modules/video_coding/packet.h"
 #include "webrtc/modules/video_coding/timing.h"
-#include "webrtc/system_wrappers/include/critical_section_wrapper.h"
 #include "webrtc/modules/video_coding/include/video_coding.h"
 #include "webrtc/modules/video_coding/include/video_coding_defines.h"
 
@@ -91,7 +91,7 @@ class VCMReceiver {
   void TriggerDecoderShutdown();
 
  private:
-  CriticalSectionWrapper* crit_sect_;
+  rtc::CriticalSection crit_sect_;
   Clock* const clock_;
   VCMJitterBuffer jitter_buffer_;
   VCMTiming* timing_;
diff --git a/webrtc/modules/video_coding/timing.cc b/webrtc/modules/video_coding/timing.cc
index f30976fd44..21f4a3dc71 100644
--- a/webrtc/modules/video_coding/timing.cc
+++ b/webrtc/modules/video_coding/timing.cc
@@ -21,22 +21,21 @@
 namespace webrtc {
 
 VCMTiming::VCMTiming(Clock* clock, VCMTiming* master_timing)
-    : crit_sect_(CriticalSectionWrapper::CreateCriticalSection()),
-      clock_(clock),
-      master_(false),
-      ts_extrapolator_(),
-      codec_timer_(new VCMCodecTimer()),
-      render_delay_ms_(kDefaultRenderDelayMs),
-      min_playout_delay_ms_(0),
-      max_playout_delay_ms_(10000),
-      jitter_delay_ms_(0),
-      current_delay_ms_(0),
-      last_decode_ms_(0),
-      prev_frame_timestamp_(0),
-      num_decoded_frames_(0),
-      num_delayed_decoded_frames_(0),
-      first_decoded_frame_ms_(-1),
-      sum_missed_render_deadline_ms_(0) {
+  : clock_(clock),
+    master_(false),
+    ts_extrapolator_(),
+    codec_timer_(new VCMCodecTimer()),
+    render_delay_ms_(kDefaultRenderDelayMs),
+    min_playout_delay_ms_(0),
+    max_playout_delay_ms_(10000),
+    jitter_delay_ms_(0),
+    current_delay_ms_(0),
+    last_decode_ms_(0),
+    prev_frame_timestamp_(0),
+    num_decoded_frames_(0),
+    num_delayed_decoded_frames_(0),
+    first_decoded_frame_ms_(-1),
+    sum_missed_render_deadline_ms_(0) {
   if (master_timing == NULL) {
     master_ = true;
     ts_extrapolator_ = new TimestampExtrapolator(clock_->TimeInMilliseconds());
@@ -50,11 +49,10 @@ VCMTiming::~VCMTiming() {
   if (master_) {
     delete ts_extrapolator_;
   }
-  delete crit_sect_;
 }
 
 void VCMTiming::UpdateHistograms() const {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   if (num_decoded_frames_ == 0) {
     return;
   }
@@ -77,7 +75,7 @@ void VCMTiming::UpdateHistograms() const {
 }
 
 void VCMTiming::Reset() {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   ts_extrapolator_->Reset(clock_->TimeInMilliseconds());
   codec_timer_.reset(new VCMCodecTimer());
   render_delay_ms_ = kDefaultRenderDelayMs;
@@ -88,37 +86,37 @@ void VCMTiming::Reset() {
 }
 
 void VCMTiming::ResetDecodeTime() {
-  CriticalSectionScoped lock(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   codec_timer_.reset(new VCMCodecTimer());
 }
 
 void VCMTiming::set_render_delay(int render_delay_ms) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   render_delay_ms_ = render_delay_ms;
 }
 
 void VCMTiming::set_min_playout_delay(int min_playout_delay_ms) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   min_playout_delay_ms_ = min_playout_delay_ms;
 }
 
 int VCMTiming::min_playout_delay() {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   return min_playout_delay_ms_;
 }
 
 void VCMTiming::set_max_playout_delay(int max_playout_delay_ms) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   max_playout_delay_ms_ = max_playout_delay_ms;
 }
 
 int VCMTiming::max_playout_delay() {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   return max_playout_delay_ms_;
 }
 
 void VCMTiming::SetJitterDelay(int jitter_delay_ms) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   if (jitter_delay_ms != jitter_delay_ms_) {
     jitter_delay_ms_ = jitter_delay_ms;
     // When in initial state, set current delay to minimum delay.
@@ -129,7 +127,7 @@ void VCMTiming::SetJitterDelay(int jitter_delay_ms) {
 }
 
 void VCMTiming::UpdateCurrentDelay(uint32_t frame_timestamp) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   int target_delay_ms = TargetDelayInternal();
 
   if (current_delay_ms_ == 0) {
@@ -171,7 +169,7 @@ void VCMTiming::UpdateCurrentDelay(uint32_t frame_timestamp) {
 
 void VCMTiming::UpdateCurrentDelay(int64_t render_time_ms,
                                    int64_t actual_decode_time_ms) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   uint32_t target_delay_ms = TargetDelayInternal();
   int64_t delayed_ms =
       actual_decode_time_ms -
@@ -190,7 +188,7 @@ int32_t VCMTiming::StopDecodeTimer(uint32_t time_stamp,
                                    int32_t decode_time_ms,
                                    int64_t now_ms,
                                    int64_t render_time_ms) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   codec_timer_->AddTiming(decode_time_ms, now_ms);
   assert(decode_time_ms >= 0);
   last_decode_ms_ = decode_time_ms;
@@ -209,13 +207,13 @@ int32_t VCMTiming::StopDecodeTimer(uint32_t time_stamp,
 }
 
 void VCMTiming::IncomingTimestamp(uint32_t time_stamp, int64_t now_ms) {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   ts_extrapolator_->Update(now_ms, time_stamp);
 }
 
 int64_t VCMTiming::RenderTimeMs(uint32_t frame_timestamp,
                                 int64_t now_ms) const {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   const int64_t render_time_ms = RenderTimeMsInternal(frame_timestamp, now_ms);
   return render_time_ms;
 }
@@ -249,7 +247,7 @@ int VCMTiming::RequiredDecodeTimeMs() const {
 
 uint32_t VCMTiming::MaxWaitingTime(int64_t render_time_ms,
                                    int64_t now_ms) const {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
 
   const int64_t max_wait_time_ms =
       render_time_ms - now_ms - RequiredDecodeTimeMs() - render_delay_ms_;
@@ -262,7 +260,7 @@ uint32_t VCMTiming::MaxWaitingTime(int64_t render_time_ms,
 
 bool VCMTiming::EnoughTimeToDecode(
     uint32_t available_processing_time_ms) const {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   int64_t required_decode_time_ms = RequiredDecodeTimeMs();
   if (required_decode_time_ms < 0) {
     // Haven't decoded any frames yet, try decoding one to get an estimate
@@ -279,7 +277,7 @@ bool VCMTiming::EnoughTimeToDecode(
 }
 
 int VCMTiming::TargetVideoDelay() const {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   return TargetDelayInternal();
 }
 
@@ -295,7 +293,7 @@ bool VCMTiming::GetTimings(int* decode_ms,
                            int* jitter_buffer_ms,
                            int* min_playout_delay_ms,
                            int* render_delay_ms) const {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   *decode_ms = last_decode_ms_;
   *max_decode_ms = RequiredDecodeTimeMs();
   *current_delay_ms = current_delay_ms_;
diff --git a/webrtc/modules/video_coding/timing.h b/webrtc/modules/video_coding/timing.h
index 429c2825f5..bfd6778c12 100644
--- a/webrtc/modules/video_coding/timing.h
+++ b/webrtc/modules/video_coding/timing.h
@@ -13,9 +13,9 @@
 
 #include <memory>
 
+#include "webrtc/base/criticalsection.h"
 #include "webrtc/base/thread_annotations.h"
 #include "webrtc/modules/video_coding/codec_timer.h"
-#include "webrtc/system_wrappers/include/critical_section_wrapper.h"
 #include "webrtc/typedefs.h"
 
 namespace webrtc {
@@ -114,7 +114,7 @@ class VCMTiming {
  private:
   void UpdateHistograms() const;
 
-  CriticalSectionWrapper* crit_sect_;
+  rtc::CriticalSection crit_sect_;
   Clock* const clock_;
   bool master_ GUARDED_BY(crit_sect_);
   TimestampExtrapolator* ts_extrapolator_ GUARDED_BY(crit_sect_);
diff --git a/webrtc/modules/video_coding/video_coding_impl.cc b/webrtc/modules/video_coding/video_coding_impl.cc
index a1cfc07af8..8ff5482af4 100644
--- a/webrtc/modules/video_coding/video_coding_impl.cc
+++ b/webrtc/modules/video_coding/video_coding_impl.cc
@@ -50,21 +50,19 @@ namespace {
 // a register method all the way down to the function calling it.
 class EncodedImageCallbackWrapper : public EncodedImageCallback {
  public:
-  EncodedImageCallbackWrapper()
-      : cs_(CriticalSectionWrapper::CreateCriticalSection()),
-        callback_(nullptr) {}
+  EncodedImageCallbackWrapper() : callback_(nullptr) {}
 
   virtual ~EncodedImageCallbackWrapper() {}
 
   void Register(EncodedImageCallback* callback) {
-    CriticalSectionScoped cs(cs_.get());
+    rtc::CritScope lock(&cs_);
     callback_ = callback;
   }
 
   virtual Result OnEncodedImage(const EncodedImage& encoded_image,
                                 const CodecSpecificInfo* codec_specific_info,
                                 const RTPFragmentationHeader* fragmentation) {
-    CriticalSectionScoped cs(cs_.get());
+    rtc::CritScope lock(&cs_);
     if (callback_) {
       return callback_->OnEncodedImage(encoded_image, codec_specific_info,
                                        fragmentation);
@@ -73,7 +71,7 @@ class EncodedImageCallbackWrapper : public EncodedImageCallback {
   }
 
  private:
-  std::unique_ptr<CriticalSectionWrapper> cs_;
+  rtc::CriticalSection cs_;
   EncodedImageCallback* callback_ GUARDED_BY(cs_);
 };
 
diff --git a/webrtc/system_wrappers/include/static_instance.h b/webrtc/system_wrappers/include/static_instance.h
index 41946d9230..e9bf81d951 100644
--- a/webrtc/system_wrappers/include/static_instance.h
+++ b/webrtc/system_wrappers/include/static_instance.h
@@ -13,7 +13,7 @@
 
 #include <assert.h>
 
-#include "webrtc/system_wrappers/include/critical_section_wrapper.h"
+#include "webrtc/base/criticalsection.h"
 #ifdef _WIN32
 #include "webrtc/system_wrappers/include/fix_interlocked_exchange_pointer_win.h"
 #endif
@@ -40,14 +40,8 @@ static T* GetStaticInstance(CountOperation count_operation) {
   static T* volatile instance = NULL;
   CreateOperation state = kInstanceExists;
 #ifndef _WIN32
-  // This memory is staticly allocated once. The application does not try to
-  // free this memory. This approach is taken to avoid issues with
-  // destruction order for statically allocated memory. The memory will be
-  // reclaimed by the OS and memory leak tools will not recognize memory
-  // reachable from statics leaked so no noise is added by doing this.
-  static CriticalSectionWrapper* crit_sect(
-    CriticalSectionWrapper::CreateCriticalSection());
-  CriticalSectionScoped lock(crit_sect);
+  rtc::CriticalSection crit_sect;
+  rtc::CritScope lock(&crit_sect);
 
   if (count_operation ==
       kAddRefNoCreate && instance_count == 0) {
@@ -77,13 +71,13 @@ static T* GetStaticInstance(CountOperation count_operation) {
     // since the thread owned by the tracing class also traces).
     // TODO(hellner): this is a bit out of place but here goes, de-couple
     // thread implementation with trace implementation.
-    crit_sect->Leave();
+    crit_sect.Leave();
     if (old_instance) {
       delete old_instance;
     }
     // Re-acquire the lock since the scoped critical section will release
     // it.
-    crit_sect->Enter();
+    crit_sect.Enter();
     return NULL;
   }
 #else  // _WIN32
diff --git a/webrtc/system_wrappers/source/trace_posix.cc b/webrtc/system_wrappers/source/trace_posix.cc
index cb702d8cea..f181ad2177 100644
--- a/webrtc/system_wrappers/source/trace_posix.cc
+++ b/webrtc/system_wrappers/source/trace_posix.cc
@@ -19,17 +19,12 @@
 
 namespace webrtc {
 
-TracePosix::TracePosix()
-    : crit_sect_(*CriticalSectionWrapper::CreateCriticalSection()) {
+TracePosix::TracePosix() {
   struct timeval system_time_high_res;
   gettimeofday(&system_time_high_res, 0);
   prev_api_tick_count_ = prev_tick_count_ = system_time_high_res.tv_sec;
 }
 
-TracePosix::~TracePosix() {
-  delete &crit_sect_;
-}
-
 int32_t TracePosix::AddTime(char* trace_message, const TraceLevel level) const {
   struct timeval system_time_high_res;
   if (gettimeofday(&system_time_high_res, 0) == -1) {
@@ -42,7 +37,7 @@ int32_t TracePosix::AddTime(char* trace_message, const TraceLevel level) const {
   const uint32_t ms_time = system_time_high_res.tv_usec / 1000;
   uint32_t prev_tickCount = 0;
   {
-    CriticalSectionScoped lock(&crit_sect_);
+    rtc::CritScope lock(&crit_sect_);
     if (level == kTraceApiCall) {
       prev_tickCount = prev_tick_count_;
       prev_tick_count_ = ms_time;
diff --git a/webrtc/system_wrappers/source/trace_posix.h b/webrtc/system_wrappers/source/trace_posix.h
index 25dfeec079..9da71039c9 100644
--- a/webrtc/system_wrappers/source/trace_posix.h
+++ b/webrtc/system_wrappers/source/trace_posix.h
@@ -11,7 +11,7 @@
 #ifndef WEBRTC_SYSTEM_WRAPPERS_SOURCE_TRACE_POSIX_H_
 #define WEBRTC_SYSTEM_WRAPPERS_SOURCE_TRACE_POSIX_H_
 
-#include "webrtc/system_wrappers/include/critical_section_wrapper.h"
+#include "webrtc/base/criticalsection.h"
 #include "webrtc/system_wrappers/source/trace_impl.h"
 
 namespace webrtc {
@@ -19,7 +19,7 @@ namespace webrtc {
 class TracePosix : public TraceImpl {
  public:
   TracePosix();
-  ~TracePosix() override;
+  ~TracePosix() override = default;
 
   // This method can be called on several different threads different from
   // the creating thread.
@@ -31,7 +31,7 @@ class TracePosix : public TraceImpl {
   volatile mutable uint32_t  prev_api_tick_count_;
   volatile mutable uint32_t  prev_tick_count_;
 
-  CriticalSectionWrapper& crit_sect_;
+  rtc::CriticalSection crit_sect_;
 };
 
 }  // namespace webrtc
diff --git a/webrtc/test/fake_network_pipe.h b/webrtc/test/fake_network_pipe.h
index 23521248f7..0c73e85e1e 100644
--- a/webrtc/test/fake_network_pipe.h
+++ b/webrtc/test/fake_network_pipe.h
@@ -24,7 +24,6 @@
 namespace webrtc {
 
 class Clock;
-class CriticalSectionWrapper;
 class PacketReceiver;
 
 class NetworkPacket {
diff --git a/webrtc/test/frame_generator_capturer.h b/webrtc/test/frame_generator_capturer.h
index 75e48497be..3b2355ff0d 100644
--- a/webrtc/test/frame_generator_capturer.h
+++ b/webrtc/test/frame_generator_capturer.h
@@ -21,7 +21,6 @@
 
 namespace webrtc {
 
-class CriticalSectionWrapper;
 class EventTimerWrapper;
 
 namespace test {
diff --git a/webrtc/voice_engine/file_recorder.cc b/webrtc/voice_engine/file_recorder.cc
index 9a0edb057b..9e1d5397bd 100644
--- a/webrtc/voice_engine/file_recorder.cc
+++ b/webrtc/voice_engine/file_recorder.cc
@@ -32,8 +32,6 @@ enum { MAX_AUDIO_BUFFER_IN_SAMPLES = 60 * 32 };
 enum { MAX_AUDIO_BUFFER_IN_BYTES = MAX_AUDIO_BUFFER_IN_SAMPLES * 2 };
 enum { kMaxAudioBufferQueueLength = 100 };
 
-class CriticalSectionWrapper;
-
 class FileRecorderImpl : public FileRecorder {
  public:
   FileRecorderImpl(uint32_t instanceID, FileFormats fileFormat);