[NaCl SDK] Add nacl_io and sdk_util namespaces.

native_client_sdk/src/libraries/nacl_io/mount_node.cc

 /* Copyright (c) 2012 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 "nacl_io/mount_node.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <string.h>
 #include <sys/stat.h>
 
 #include <algorithm>
 #include <string>
 
 #include "nacl_io/kernel_wrap_real.h"
 #include "nacl_io/mount.h"
 #include "nacl_io/osmman.h"
 #include "sdk_util/auto_lock.h"
 
+namespace nacl_io {
+
 static const int USR_ID = 1001;
 static const int GRP_ID = 1002;
 
 MountNode::MountNode(Mount* mount) : mount_(mount) {
   memset(&stat_, 0, sizeof(stat_));
   stat_.st_gid = GRP_ID;
   stat_.st_uid = USR_ID;
 
   // Mount should normally never be NULL, but may be null in tests.
   // If NULL, at least set the inode to a valid (nonzero) value.
@@ skipping 112 matching lines @@
   out_node->reset(NULL);
   return ENOTDIR;
 }
 
 int MountNode::ChildCount() { return 0; }
 
 void MountNode::Link() { stat_.st_nlink++; }
 
 void MountNode::Unlink() { stat_.st_nlink--; }
 
+}  // namespace nacl_io
+