Move chromeos code to namespace chromeos.

chrome/browser/chromeos/pipe_reader.cc

 // 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.
 
 #include "chrome/browser/chromeos/pipe_reader.h"
 
 #include "base/scoped_ptr.h"
 
+namespace chromeos {
+
 std::string PipeReader::Read(const uint32 bytes_to_read) {
   scoped_array<char> buffer(new char[bytes_to_read]);
   if (pipe_ || (pipe_ = fopen(pipe_name_.c_str(), "r"))) {
     const char* to_return = fgets(buffer.get(), bytes_to_read, pipe_);
     if (to_return)
       return to_return;  // auto-coerced to a std::string.
   }
   return std::string();
 }
+
+}  // namespace chromeos