[NaCl SDK] Add nacl_io and sdk_util namespaces.

native_client_sdk/src/libraries/nacl_io/mount_node_mem.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_mem.h"
 
 #include <errno.h>
 #include <string.h>
 
 #include "nacl_io/osstat.h"
 #include "sdk_util/auto_lock.h"
 
+namespace nacl_io {
+
 #define BLOCK_SIZE (1 << 16)
 #define BLOCK_MASK (BLOCK_SIZE - 1)
 
 MountNodeMem::MountNodeMem(Mount* mount)
     : MountNode(mount), data_(NULL), capacity_(0) {
   stat_.st_mode |= S_IFREG;
 }
 
 MountNodeMem::~MountNodeMem() { free(data_); }
 
@@ skipping 63 matching lines @@
 
   // If we failed, then adjust size according to what we keep
   if (new_size > capacity_)
     new_size = capacity_;
 
   // Update the size and return the new size
   stat_.st_size = static_cast<off_t>(new_size);
   return EIO;
 }
 
+}  // namespace nacl_io
+