Oilpan: Enable Oilpan in modules/encoding

Source/modules/encoding/TextDecoder.h

Index: Source/modules/encoding/TextDecoder.h
diff --git a/Source/modules/encoding/TextDecoder.h b/Source/modules/encoding/TextDecoder.h
index 4d09fc0b63a703be0c7d436eeb5b9b21a46c4a08..e630ed5540cdbc641e782c2b40bd243bb005b6eb 100644
--- a/Source/modules/encoding/TextDecoder.h
+++ b/Source/modules/encoding/TextDecoder.h
@@ -43,9 +43,9 @@ namespace WebCore {
 
 class ExceptionState;
 
-class TextDecoder FINAL : public RefCountedWillBeGarbageCollectedFinalized<TextDecoder> {
+class TextDecoder FINAL : public GarbageCollectedFinalized<TextDecoder> {
 public:
-    static PassRefPtrWillBeRawPtr<TextDecoder> create(const String& label, const Dictionary&, ExceptionState&);
+    static TextDecoder* create(const String& label, const Dictionary&, ExceptionState&);
     ~TextDecoder();
 
     // Implement the IDL