pp::FileSystem: add copy constrctor

ppapi/cpp/file_system.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 PPAPI_CPP_FILE_SYSTEM_H_
 #define PPAPI_CPP_FILE_SYSTEM_H_
 
 #include "ppapi/c/pp_file_info.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_stdint.h"
@@ skipping 10 matching lines @@
 
 /// The <code>FileSystem</code> class identifies the file system type
 /// associated with a file.
 class FileSystem : public Resource {
  public:
   /// Constructs an is_null() filesystem resource. If you use this constructor,
   /// you will have to assign it to a "real" FileSystem object before you can
   /// use it.
   FileSystem();
 
+  /// The copy constructor for <code>FileSystem</code>.
+  ///
+  /// @param[in] other A reference to a <code>FileSystem</code>.
+  FileSystem(const FileSystem& other);
+
   /// A constructor used when you have received a PP_Resource as a return
   /// value that has already been reference counted.
   ///
   /// @param[in] resource A PP_Resource corresponding to a PPB_FileSystem.
   FileSystem(PassRef, PP_Resource resource);
 
   /// This constructor creates a file system object of the given type.
   ///
   /// @param[in] instance The instance with which this resource will be
   /// associated.
@@ skipping 15 matching lines @@
   /// @param[in] cc A <code>PP_CompletionCallback</code> to be called upon
   /// completion of Open().
   ///
   /// @return An int32_t containing an error code from <code>pp_errors.h</code>.
   int32_t Open(int64_t expected_size, const CompletionCallback& cc);
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_FILE_SYSTEM_H_