Demistify DocumentParser::append

Source/core/dom/DocumentParser.h

Index: Source/core/dom/DocumentParser.h
diff --git a/Source/core/dom/DocumentParser.h b/Source/core/dom/DocumentParser.h
index 2863cb73eb4b33c234f49164834758cd82d74c79..2bd668c60715a5e9ab299e9e05ba9eb92b8d65ed 100644
--- a/Source/core/dom/DocumentParser.h
+++ b/Source/core/dom/DocumentParser.h
@@ -56,10 +56,8 @@ public:
     virtual TextResourceDecoder* decoder();
     virtual void setHasAppendedData() { }
 
-    // FIXME: append() should be private, but DocumentLoader::replaceDocumentWhileExecutingJavaScriptURL uses it for now.
-    // FIXME: This really should take a PassOwnPtr to signify that it expects to take
-    // ownership of the buffer. The parser expects the PassRefPtr to hold the only ref of the StringImpl.
-    virtual void append(PassRefPtr<StringImpl>) = 0;
+    // FIXME: append() should be private, but DocumentLoader and DOMPatchSupport uses it for now.
+    virtual void append(const String&) = 0;
 
     virtual void finish() = 0;