Oilpan: make DocumentFragment a heap allocated object.

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 b6408dbe829ec2b970dc6ff389cfef35a7911e0e..a65ba8bddcefa29492ddfc3bb9f77fd61488f435 100644
--- a/Source/core/xml/XSLTProcessor.cpp
+++ b/Source/core/xml/XSLTProcessor.cpp
@@ -114,7 +114,7 @@ PassRefPtr<Document> XSLTProcessor::transformToDocument(Node* sourceNode)
     return createDocumentFromSource(resultString, resultEncoding, resultMIMEType, sourceNode, 0);
 }
 
-PassRefPtr<DocumentFragment> XSLTProcessor::transformToFragment(Node* sourceNode, Document* outputDoc)
+PassRefPtrWillBeRawPtr<DocumentFragment> XSLTProcessor::transformToFragment(Node* sourceNode, Document* outputDoc)
 {
     if (!sourceNode || !outputDoc)
         return nullptr;