Replace rtc::ThreadChecker with webrtc::SequenceChecker

Bug: webrtc:12419
Change-Id: I825c014cc1c4b1dcba5ef300409d44859e971144
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/205002
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Tommi <tommi@webrtc.org>
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33136}
diff --git a/modules/video_coding/video_coding_impl.h b/modules/video_coding/video_coding_impl.h
index aee6337..d8b0225 100644
--- a/modules/video_coding/video_coding_impl.h
+++ b/modules/video_coding/video_coding_impl.h
@@ -27,7 +27,6 @@
 #include "rtc_base/synchronization/mutex.h"
 #include "rtc_base/synchronization/sequence_checker.h"
 #include "rtc_base/thread_annotations.h"
-#include "rtc_base/thread_checker.h"
 #include "system_wrappers/include/clock.h"
 
 namespace webrtc {
@@ -97,9 +96,9 @@
   // In builds where DCHECKs aren't enabled, it will return true.
   bool IsDecoderThreadRunning();
 
-  rtc::ThreadChecker construction_thread_checker_;
-  rtc::ThreadChecker decoder_thread_checker_;
-  rtc::ThreadChecker module_thread_checker_;
+  SequenceChecker construction_thread_checker_;
+  SequenceChecker decoder_thread_checker_;
+  SequenceChecker module_thread_checker_;
   Clock* const clock_;
   Mutex process_mutex_;
   VCMTiming* _timing;