Some description changes and documentation for logging.h

ppapi/cpp/instance.h

 // Copyright (c) 2011 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_INSTANCE_H_
 #define PPAPI_CPP_INSTANCE_H_
 
 /// @file
-/// Defines the C++ wrapper for an instance.
+/// This file defines the C++ wrapper for an instance.
 
 #include <map>
 #include <string>
 
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/c/pp_stdint.h"
 
 struct PP_InputEvent;
 
@@ skipping 491 matching lines @@
  private:
   PP_Instance pp_instance_;
 
   typedef std::map<std::string, void*> InterfaceNameToObjectMap;
   InterfaceNameToObjectMap interface_name_to_objects_;
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_INSTANCE_H_