Move chromeos code to namespace chromeos.

chrome/browser/chromeos/pipe_reader.h

Index: chrome/browser/chromeos/pipe_reader.h
===================================================================
--- chrome/browser/chromeos/pipe_reader.h	(revision 30488)
+++ chrome/browser/chromeos/pipe_reader.h	(working copy)
@@ -7,13 +7,16 @@
 
 #include <fcntl.h>
 #include <stdio.h>
-#include <string>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
 
+#include <string>
+
 #include "base/basictypes.h"
 
+namespace chromeos {
+
 // Given a named pipe, this class reads data from it and returns it as a string.
 // Currently, we are sending login cookies from the Chrome OS login manager to
 // Chrome over a named Unix pipe.  We want to replace this with DBus, but
@@ -48,4 +51,6 @@
   DISALLOW_COPY_AND_ASSIGN(PipeReader);
 };
 
+}  // namespace chromeos
+
 #endif  // CHROME_BROWSER_CHROMEOS_PIPE_READER_H_