Fix compiling of sync on linux.

chrome/browser/sync/util/compat_pthread.h

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Pthread compatability routines.
 // TODO(timsteele): This file is deprecated. Use PlatformThread.
 
 #ifndef CHROME_BROWSER_SYNC_UTIL_COMPAT_PTHREAD_H_
 #define CHROME_BROWSER_SYNC_UTIL_COMPAT_PTHREAD_H_
 
 #include "base/platform_thread.h"
 #include "build/build_config.h"
 
 #define ThreadId PlatformThreadId
 
 #ifndef OS_WIN
 inline ThreadId GetCurrentThreadId() {
   return PlatformThread::CurrentId();
 }
 #endif  // OS_WIN
 
-#if (!defined(OS_WIN) && !defined(OS_MACOSX))
-// TODO(timsteele): What the heck is this?
-inline int sem_post_multiple(sem_t* sem, int number) {
-  int i;
-  int r = 0;
-  for (i = 0; i < number; i++) {
-    r = sem_post(sem);
-    if (r != 0) {
-      LOG_IF(ERROR, i > 0) << "sem_post() failed on iteration #" << i <<
-        " of " << number;
-      return r;
-    }
-  }
-  return 0;
-}
-#endif  // (!defined(OS_WIN) && !defined(OS_MACOSX))
-
 #endif  // CHROME_BROWSER_SYNC_UTIL_COMPAT_PTHREAD_H_