[NaCl SDK] Add nacl_io and sdk_util namespaces.

native_client_sdk/src/libraries/nacl_io/pepper_interface.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/pepper_interface.h"
 #include <errno.h>
 #include <ppapi/c/pp_errors.h>
 
+namespace nacl_io {
+
 ScopedResource::ScopedResource(PepperInterface* ppapi, PP_Resource resource)
     : ppapi_(ppapi),
       resource_(resource) {
 }
 
 ScopedResource::~ScopedResource() {
   if (resource_)
     ppapi_->ReleaseResource(resource_);
 }
 
@@ skipping 27 matching lines @@
     case PP_ERROR_USERCANCEL: return EPERM;
     case PP_ERROR_NO_USER_GESTURE: return EPERM;
     case PP_ERROR_CONTEXT_LOST: return EPERM;
     case PP_ERROR_NO_MESSAGE_LOOP: return EPERM;
     case PP_ERROR_WRONG_THREAD: return EPERM;
   }
 
   return EINVAL;
 }
 
+}  // namespace nacl_io