Oilpan: have xml/ objects on the heap by default.

Source/core/inspector/InspectorDOMAgent.cpp

Index: Source/core/inspector/InspectorDOMAgent.cpp
diff --git a/Source/core/inspector/InspectorDOMAgent.cpp b/Source/core/inspector/InspectorDOMAgent.cpp
index fffd8b1e82eee1595d05c99e60526a625ab3a75f..e35a68f2a58264647d6e9e20458dc9b8f181c32a 100644
--- a/Source/core/inspector/InspectorDOMAgent.cpp
+++ b/Source/core/inspector/InspectorDOMAgent.cpp
@@ -1073,7 +1073,7 @@ void InspectorDOMAgent::performSearch(ErrorString*, const String& whitespaceTrim
         for (Document* document : docs) {
             ASSERT(document);
             TrackExceptionState exceptionState;
-            RefPtrWillBeRawPtr<XPathResult> result = DocumentXPathEvaluator::evaluate(*document, whitespaceTrimmedQuery, document, nullptr, XPathResult::ORDERED_NODE_SNAPSHOT_TYPE, ScriptValue(), exceptionState);
+            XPathResult* result = DocumentXPathEvaluator::evaluate(*document, whitespaceTrimmedQuery, document, nullptr, XPathResult::ORDERED_NODE_SNAPSHOT_TYPE, ScriptValue(), exceptionState);
             if (exceptionState.hadException() || !result)
                 continue;