Remove unused ConditionVariableWrapper on POSIX platforms

webrtc/system_wrappers/source/condition_variable.cc

 /*
  *  Copyright (c) 2011 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 "webrtc/system_wrappers/include/condition_variable_wrapper.h"
 
-#if defined(_WIN32)
+// TODO(tommi): Remove completely.  As is there is still some code for Windows
+// that relies on ConditionVariableWrapper, but code has been removed on other
+// platforms.
+#if defined(WEBRTC_WIN)
+
 #include <windows.h>
 #include "webrtc/system_wrappers/source/condition_variable_event_win.h"
 #include "webrtc/system_wrappers/source/condition_variable_native_win.h"
-#elif defined(WEBRTC_LINUX) || defined(WEBRTC_MAC)
-#include <pthread.h>
-#include "webrtc/system_wrappers/source/condition_variable_posix.h"
-#endif
 
 namespace webrtc {
-
 ConditionVariableWrapper* ConditionVariableWrapper::CreateConditionVariable() {
-#if defined(_WIN32)
   // Try to create native condition variable implementation.
   ConditionVariableWrapper* ret_val = ConditionVariableNativeWin::Create();
   if (!ret_val) {
     // Native condition variable implementation does not exist. Create generic
     // condition variable based on events.
     ret_val = new ConditionVariableEventWin();
   }
   return ret_val;
-#elif defined(WEBRTC_LINUX) || defined(WEBRTC_MAC)
-  return ConditionVariablePosix::Create();
-#else
-  return NULL;
-#endif
 }
+}  // namespace webrtc
 
-}  // namespace webrtc
+#endif  // defined(WEBRTC_WIN)