Oilpan: keep navigation timing objects on the heap by default.

Source/core/timing/PerformanceTiming.h

Index: Source/core/timing/PerformanceTiming.h
diff --git a/Source/core/timing/PerformanceTiming.h b/Source/core/timing/PerformanceTiming.h
index 2dcf6c1023de44b3ed1cf7cd65c32d7e790f8d26..8c0220ee0705b7bd2630a6ffc87f620dba2f1ea2 100644
--- a/Source/core/timing/PerformanceTiming.h
+++ b/Source/core/timing/PerformanceTiming.h
@@ -35,8 +35,6 @@
 #include "core/CoreExport.h"
 #include "core/frame/DOMWindowProperty.h"
 #include "platform/heap/Handle.h"
-#include "wtf/PassRefPtr.h"
-#include "wtf/RefCounted.h"
 
 namespace blink {
 
@@ -46,13 +44,13 @@ class DocumentTiming;
 class LocalFrame;
 class ResourceLoadTiming;
 
-class CORE_EXPORT PerformanceTiming final : public RefCountedWillBeGarbageCollected<PerformanceTiming>, public ScriptWrappable, public DOMWindowProperty {
+class CORE_EXPORT PerformanceTiming final : public GarbageCollectedFinalized<PerformanceTiming>, public ScriptWrappable, public DOMWindowProperty {
     DEFINE_WRAPPERTYPEINFO();
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(PerformanceTiming);
 public:
-    static PassRefPtrWillBeRawPtr<PerformanceTiming> create(LocalFrame* frame)
+    static PerformanceTiming* create(LocalFrame* frame)
     {
-        return adoptRefWillBeNoop(new PerformanceTiming(frame));
+        return new PerformanceTiming(frame);
     }
 
     unsigned long long navigationStart() const;