Issue 4125 - [emscripten] Convert filter classes to C++

compiled/ElemHideBase.h

-#ifndef ADBLOCK_PLUS_ELEM_HIDE_BASE_H
-#define ADBLOCK_PLUS_ELEM_HIDE_BASE_H
+#pragma once
 
 #include <cstddef>
 
 #include "ActiveFilter.h"
 
 struct ElemHideBaseData
 {
   String::size_type mDomainsEnd;
   String::size_type mSelectorStart;
 
@@ skipping 18 matching lines @@
   }
 
   const DependentString GetSelector(const String& text) const
   {
     return DependentString(text, mSelectorStart);
   }
 };
 
 struct ElemHideData;
 
-class ElemHideBase : public ActiveFilter, protected ElemHideBaseData
+class ElemHideBase : public ActiveFilter
 {
+protected:
+  ElemHideBaseData mData;
 public:
-  ElemHideBase(const String& text, const ElemHideBaseData& data);
+  explicit ElemHideBase(Type type, const String& text, const ElemHideBaseData& data);
   static Type Parse(DependentString& text, ElemHideData& data);
 
   EMSCRIPTEN_KEEPALIVE const DependentString GetSelector() const
   {
-    return ElemHideBaseData::GetSelector(mText);
+    return mData.GetSelector(mText);
   }
 
   EMSCRIPTEN_KEEPALIVE OwnedString GetSelectorDomain() const;
 };
-
-#endif