Remove some unused files

webrtc/rtc_base/synchronization/yield.cc

@@ -1,36 +0,0 @@
-/*
- *  Copyright 2020 The WebRTC Project Authors. All rights reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-#include "rtc_base/synchronization/yield.h"
-
-#if defined(WEBRTC_WIN)
-#include <windows.h>
-#else
-#include <sched.h>
-#include <time.h>
-#endif
-
-namespace webrtc {
-
-void YieldCurrentThread() {
-  // TODO(bugs.webrtc.org/11634): use dedicated OS functionality instead of
-  // sleep for yielding.
-#if defined(WEBRTC_WIN)
-  ::Sleep(0);
-#elif defined(WEBRTC_MAC) && defined(RTC_USE_NATIVE_MUTEX_ON_MAC) && \
-    !RTC_USE_NATIVE_MUTEX_ON_MAC
-  sched_yield();
-#else
-  static const struct timespec ts_null = {0};
-  nanosleep(&ts_null, nullptr);
-#endif
-}
-
-}  // namespace webrtc

webrtc/rtc_base/synchronization/yield.h

@@ -1,20 +0,0 @@
-/*
- *  Copyright 2020 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-#ifndef RTC_BASE_SYNCHRONIZATION_YIELD_H_
-#define RTC_BASE_SYNCHRONIZATION_YIELD_H_
-
-namespace webrtc {
-
-// Request rescheduling of threads.
-void YieldCurrentThread();
-
-}  // namespace webrtc
-
-#endif  // RTC_BASE_SYNCHRONIZATION_YIELD_H_