Revert of "Revert of Moved text decoding to the parser thread"

Source/core/html/parser/TextDocumentParser.h

Index: Source/core/html/parser/TextDocumentParser.h
diff --git a/Source/core/html/parser/TextDocumentParser.h b/Source/core/html/parser/TextDocumentParser.h
index 6b5bb9e6a4c7bcb10b1c645ed00acf1e61fde76b..eba5d07907e35b240b136bc0be6d6ff2569ea776 100644
--- a/Source/core/html/parser/TextDocumentParser.h
+++ b/Source/core/html/parser/TextDocumentParser.h
@@ -41,7 +41,7 @@ public:
 private:
     explicit TextDocumentParser(HTMLDocument*);
 
-    virtual void append(PassRefPtr<StringImpl>);
+    virtual void appendBytes(const char*, size_t) OVERRIDE FINAL;
     void insertFakePreElement();
 
     bool m_haveInsertedFakePreElement;