Remove deprecated ExpectationToString in SequenceChecker

Bug: webrtc:12419
Change-Id: I501b96865f69f15e49a813c5dcd6ccf44d67c2e7
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/205621
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33157}
diff --git a/rtc_base/synchronization/sequence_checker.h b/rtc_base/synchronization/sequence_checker.h
index 31314a4..abf0ebf 100644
--- a/rtc_base/synchronization/sequence_checker.h
+++ b/rtc_base/synchronization/sequence_checker.h
@@ -46,10 +46,6 @@
     : public webrtc_sequence_checker_internal::SequenceCheckerDoNothing {};
 #endif  // RTC_ENABLE_THREAD_CHECKER
 
-namespace webrtc_seq_check_impl {
-// TODO(titovartem): Remove when downstream deps are updated
-using ::webrtc::webrtc_sequence_checker_internal::SequenceCheckerScope;
-}  // namespace webrtc_seq_check_impl
 }  // namespace webrtc
 
 // RTC_RUN_ON/RTC_GUARDED_BY/RTC_DCHECK_RUN_ON macros allows to annotate
@@ -117,16 +113,6 @@
 #define RTC_RUN_ON(x) \
   RTC_THREAD_ANNOTATION_ATTRIBUTE__(exclusive_locks_required(x))
 
-namespace webrtc {
-
-// Deprecated. Do not use.
-template <typename ThreadLikeObject>
-RTC_DEPRECATED std::string ExpectationToString(const ThreadLikeObject* o) {
-  return webrtc::webrtc_sequence_checker_internal::ExpectationToString(o);
-}
-
-}  // namespace webrtc
-
 #define RTC_DCHECK_RUN_ON(x)                                               \
   webrtc::webrtc_sequence_checker_internal::SequenceCheckerScope scope(x); \
   RTC_DCHECK((x)->IsCurrent())                                             \