Noissue - [emscripten] Address compiler warnings

compiled/StringMap.h

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2017 eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 301 matching lines @@
 template<typename T>
 class StringMap
   : public StringMap_internal::HashContainer<StringMap_internal::StringMapEntry<T>>
 {
 public:
   typedef StringMap_internal::HashContainer<StringMap_internal::StringMapEntry<T>> super;
   typedef typename super::size_type size_type;
   typedef typename super::entry_type entry_type;
   typedef typename super::const_reference const_reference;
   typedef StringMap_internal::StringMapEntryReference<T> reference;
-  friend class StringMap_internal::StringMapEntryReference<T>;
+  friend struct StringMap_internal::StringMapEntryReference<T>;
 
   explicit StringMap(size_type expectedEntries = 0)
       : super(expectedEntries)
   {
   }
 
   StringMap(std::initializer_list<entry_type> list)
       : super(list.size())
   {
     for (const auto& item : list)
@@ skipping 15 matching lines @@
   const_reference find(const String& key) const
   {
     return super::find(key);
   }
 
   reference find(const String& key)
   {
     return reference(this, key, super::find_bucket(key));
   }
 };