DocType strings should be 8 bit wide

Source/core/html/parser/HTMLConstructionSite.cpp

Index: Source/core/html/parser/HTMLConstructionSite.cpp
diff --git a/Source/core/html/parser/HTMLConstructionSite.cpp b/Source/core/html/parser/HTMLConstructionSite.cpp
index 4cecc3db4d99c44d5206d76ed647ef166d2a9986..96d3025240f3549ab78e3f2fdb2d2c1581e72e93 100644
--- a/Source/core/html/parser/HTMLConstructionSite.cpp
+++ b/Source/core/html/parser/HTMLConstructionSite.cpp
@@ -421,8 +421,8 @@ void HTMLConstructionSite::insertDoctype(AtomicHTMLToken* token)
 {
     ASSERT(token->type() == HTMLToken::DOCTYPE);
 
-    const String& publicId = String::adopt(token->publicIdentifier());
-    const String& systemId = String::adopt(token->systemIdentifier());
+    const String& publicId = StringImpl::create8BitIfPossible(token->publicIdentifier());
+    const String& systemId = StringImpl::create8BitIfPossible(token->systemIdentifier());
     RefPtr<DocumentType> doctype = DocumentType::create(m_document, token->name(), publicId, systemId);
     attachLater(m_attachmentRoot, doctype.release());