Add an extra guard to replaceDocument()

Source/core/loader/DocumentLoader.h

Index: Source/core/loader/DocumentLoader.h
diff --git a/Source/core/loader/DocumentLoader.h b/Source/core/loader/DocumentLoader.h
index 1406584a11bfd900398258c84350db4daa7dce3c..fbeac1744509d5d1fb7a5643d35d874fa4b1699d 100644
--- a/Source/core/loader/DocumentLoader.h
+++ b/Source/core/loader/DocumentLoader.h
@@ -57,6 +57,7 @@ namespace blink {
     class ArchiveResourceCollection;
     class ResourceFetcher;
     class ContentFilter;
+    class DocumentInit;
     class FormState;
     class LocalFrame;
     class FrameLoader;
@@ -80,7 +81,7 @@ namespace blink {
 
         unsigned long mainResourceIdentifier() const;
 
-        void replaceDocument(const String& source, Document*);
+        void replaceDocument(const DocumentInit&, const String& source, Document*);
 
         const AtomicString& mimeType() const;
 
@@ -142,6 +143,7 @@ namespace blink {
 
     private:
         static PassRefPtrWillBeRawPtr<DocumentWriter> createWriterFor(LocalFrame*, const Document* ownerDocument, const KURL&, const AtomicString& mimeType, const AtomicString& encoding, bool dispatch);
+        static PassRefPtrWillBeRawPtr<DocumentWriter> createWriterFor(const Document* ownerDocument, const DocumentInit&, const AtomicString& mimeType, const AtomicString& encoding, bool dispatch);
 
         void ensureWriter(const AtomicString& mimeType, const KURL& overridingURL = KURL());
         void endWriting(DocumentWriter*);