remove more CriticalSectionWrappers.

BUG=webrtc:7035

Review-Url: https://codereview.webrtc.org/2779623002
Cr-Commit-Position: refs/heads/master@{#17392}
diff --git a/webrtc/modules/video_coding/receiver.cc b/webrtc/modules/video_coding/receiver.cc
index 826647c..af9ddb8 100644
--- a/webrtc/modules/video_coding/receiver.cc
+++ b/webrtc/modules/video_coding/receiver.cc
@@ -72,8 +72,7 @@
                          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() {
   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::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 @@
 }
 
 VCMNackMode VCMReceiver::NackMode() const {
-  CriticalSectionScoped cs(crit_sect_);
+  rtc::CritScope cs(&crit_sect_);
   return jitter_buffer_.nack_mode();
 }
 
@@ -273,7 +271,7 @@
 }
 
 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;
   }