Issue 6180 - use ABP_TEXT everywhere in order to let String be a UTF-8 string

compiled/ElemHide.cpp

 /*
  * 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 213 matching lines @@
 
         auto filter = entry.second;
         if (filter && !GetException(*filter, docDomain))
           selectors->push_back(filter);
       }
     }
 
     if (currentDomain.empty())
       break;
 
-    auto nextDot = currentDomain.find(u'.');
+    auto nextDot = currentDomain.find(ABP_TEXT('.'));
     currentDomain = nextDot == String::npos ?
-      u""_str : DependentString(currentDomain, nextDot + 1);
+      ABP_TEXT(""_str) : DependentString(currentDomain, nextDot + 1);
   }
 
   return selectors.release();
 }