Issue 5141 - Convert filter match to C++

compiled/StringMap.h

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present 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 219 matching lines @@
 
     const_iterator end() const
     {
       return const_iterator(&mBuckets[mBucketCount], &mBuckets[mBucketCount]);
     }
 
     size_type size() const
     {
       return mEntryCount;
     }
+
+    void clear()
+    {
+      resize(0);
+    }
   };
 
   struct StringSetEntry
   {
     StringSetEntry() {}
     StringSetEntry(const String& key)
         : first(key)
     {
     }
 
@@ skipping 98 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));
   }
 };