Implement a part of ProcessingInstruction by using PrivateScript

Source/core/xml/XSLTProcessor.cpp

Index: Source/core/xml/XSLTProcessor.cpp
diff --git a/Source/core/xml/XSLTProcessor.cpp b/Source/core/xml/XSLTProcessor.cpp
index ea0f323016dca3baacf69d371fd16e046656c2fb..fe6ad332a249dd4f890da7f1ce0da66501ff7ef7 100644
--- a/Source/core/xml/XSLTProcessor.cpp
+++ b/Source/core/xml/XSLTProcessor.cpp
@@ -23,9 +23,11 @@
 #include "config.h"
 #include "core/xml/XSLTProcessor.h"
 
+#include "bindings/core/v8/V8Document.h"
 #include "core/dom/DOMImplementation.h"
 #include "core/dom/DocumentEncodingData.h"
 #include "core/dom/DocumentFragment.h"
+#include "core/dom/ProcessingInstruction.h"
 #include "core/editing/markup.h"
 #include "core/frame/LocalDOMWindow.h"
 #include "core/frame/FrameView.h"
@@ -83,7 +85,10 @@ PassRefPtrWillBeRawPtr<Document> XSLTProcessor::createDocumentFromSource(const S
             view->clear();
 
         if (oldDocument) {
-            result->setTransformSourceDocument(oldDocument.get());
+            if (RuntimeEnabledFeatures::xsltInPrivateScriptEnabled())
+                V8Document::PrivateScript::setTransformSourceDocumentMethod(frame, result.get(), oldDocument.get());
+            else
+                result->setTransformSourceDocument(oldDocument.get());
             result->updateSecurityOrigin(oldDocument->securityOrigin());
             result->setCookieURL(oldDocument->cookieURL());
             result->contentSecurityPolicy()->copyStateFrom(oldDocument->contentSecurityPolicy());