Oilpan: Build fix after r170314

Source/core/html/parser/HTMLPreloadScanner.cpp

Index: Source/core/html/parser/HTMLPreloadScanner.cpp
diff --git a/Source/core/html/parser/HTMLPreloadScanner.cpp b/Source/core/html/parser/HTMLPreloadScanner.cpp
index e52a5763faff0d7a9332d54ef7e31066946c66bb..102f22371ce7d296df2be3b041ad9002a2c1aa83 100644
--- a/Source/core/html/parser/HTMLPreloadScanner.cpp
+++ b/Source/core/html/parser/HTMLPreloadScanner.cpp
@@ -95,7 +95,7 @@ static String initiatorFor(const StringImpl* tagImpl)
 
 static bool mediaAttributeMatches(const MediaValues& mediaValues, const String& attributeValue)
 {
-    RefPtr<MediaQuerySet> mediaQueries = MediaQuerySet::create(attributeValue);
+    RefPtrWillBeRawPtr<MediaQuerySet> mediaQueries = MediaQuerySet::create(attributeValue);
     MediaQueryEvaluator mediaQueryEvaluator("screen", mediaValues);
     return mediaQueryEvaluator.eval(mediaQueries.get());
 }