[NaCl SDK] Add nacl_io and sdk_util namespaces.

native_client_sdk/src/libraries/nacl_io/mount_http.h

 /* 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.
  */
 
 #ifndef LIBRARIES_NACL_IO_MOUNT_HTTP_H_
 #define LIBRARIES_NACL_IO_MOUNT_HTTP_H_
 
 #include <string>
 #include "nacl_io/mount.h"
 #include "nacl_io/pepper_interface.h"
 #include "nacl_io/typed_mount_factory.h"
 
+class MountHttpMock;
+
+namespace nacl_io {
+
 class MountNode;
-class MountHttpMock;
 
 std::string NormalizeHeaderKey(const std::string& s);
 
 class MountHttp : public Mount {
  public:
   typedef std::map<std::string, ScopedMountNode> NodeMap_t;
 
   virtual Error Access(const Path& path, int a_mode);
   virtual Error Open(const Path& path, int mode, ScopedMountNode* out_node);
   virtual Error Unlink(const Path& path);
@@ skipping 22 matching lines @@
   std::string url_root_;
   StringMap_t headers_;
   NodeMap_t node_cache_;
   bool allow_cors_;
   bool allow_credentials_;
   bool cache_stat_;
   bool cache_content_;
 
   friend class TypedMountFactory<MountHttp>;
   friend class MountNodeHttp;
-  friend class MountHttpMock;
+  friend class ::MountHttpMock;
 };
 
+}  // namespace nacl_io
+
 #endif  // LIBRARIES_NACL_IO_MOUNT_HTTP_H_