Turn DocumentParser::pinToMainThread into a cleaner api

Source/core/inspector/DOMPatchSupport.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 78 matching lines @@
         newDocument = XMLDocument::createSVG();
     else if (document().isXHTMLDocument())
         newDocument = XMLDocument::createXHTML();
     else if (document().isXMLDocument())
         newDocument = XMLDocument::create();
 
     ASSERT(newDocument);
     newDocument->setContextFeatures(document().contextFeatures());
     if (!document().isHTMLDocument()) {
         RefPtrWillBeRawPtr<DocumentParser> parser = XMLDocumentParser::create(*newDocument, nullptr);
-        parser->pinToMainThread();
         parser->append(markup.impl());
         parser->finish();
         parser->detach();
 
         // Avoid breakage on non-well-formed documents.
         if (!static_cast<XMLDocumentParser*>(parser.get())->wellFormed())
             return;
     }
     newDocument->setContent(markup);
     OwnPtr<Digest> oldInfo = createDigest(document().documentElement(), 0);
@@ skipping 401 matching lines @@
 void DOMPatchSupport::dumpMap(const ResultMap& map, const String& name)
 {
     fprintf(stderr, "\n\n");
     for (size_t i = 0; i < map.size(); ++i)
         fprintf(stderr, "%s[%lu]: %s (%p) - [%lu]\n", name.utf8().data(), i, map[i].first ? nodeName(map[i].first->m_node).utf8().data() : "", map[i].first, map[i].second);
 }
 #endif
 
 } // namespace blink