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diff --git a/chromium/third_party/webrtc/base/filelock.h b/chromium/third_party/webrtc/base/filelock.h
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+++ b/chromium/third_party/webrtc/base/filelock.h
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+/*
+ *  Copyright 2009 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 WEBRTC_BASE_FILELOCK_H_
+#define WEBRTC_BASE_FILELOCK_H_
+
+#include <string>
+
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/base/scoped_ptr.h"
+
+namespace rtc {
+
+class FileStream;
+
+// Implements a very simple cross process lock based on a file.
+// When Lock(...) is called we try to open/create the file in read/write
+// mode without any sharing. (Or locking it with flock(...) on Unix)
+// If the process crash the OS will make sure that the file descriptor
+// is released and another process can accuire the lock.
+// This doesn't work on ancient OSX/Linux versions if used on NFS.
+// (Nfs-client before: ~2.6 and Linux Kernel < 2.6.)
+class FileLock {
+ public:
+  virtual ~FileLock();
+
+  // Attempts to lock the file. The caller owns the returned
+  // lock object. Returns NULL if the file already was locked.
+  static FileLock* TryLock(const std::string& path);
+  void Unlock();
+
+ protected:
+  FileLock(const std::string& path, FileStream* file);
+
+ private:
+  void MaybeUnlock();
+
+  std::string path_;
+  scoped_ptr<FileStream> file_;
+
+  DISALLOW_EVIL_CONSTRUCTORS(FileLock);
+};
+
+}  // namespace rtc
+
+#endif  // WEBRTC_BASE_FILELOCK_H_