Oilpan: have DOMException be on the heap by default.

Source/modules/push_messaging/PushError.h

Index: Source/modules/push_messaging/PushError.h
diff --git a/Source/modules/push_messaging/PushError.h b/Source/modules/push_messaging/PushError.h
index d7f87c3d5d4add04ad63f1aab2b53da0f1ceb027..34ac529aa1272b650f68aed1fced2712e66b7742 100644
--- a/Source/modules/push_messaging/PushError.h
+++ b/Source/modules/push_messaging/PushError.h
@@ -5,12 +5,12 @@
 #ifndef PushError_h
 #define PushError_h
 
-#include "core/dom/DOMException.h"
 #include "platform/heap/Handle.h"
 #include "public/platform/modules/push_messaging/WebPushError.h"
 
 namespace blink {
 
+class DOMException;
 class ScriptPromiseResolver;
 
 class PushError {
@@ -18,7 +18,7 @@ class PushError {
 public:
     // For CallbackPromiseAdapter.
     typedef WebPushError WebType;
-    static PassRefPtrWillBeRawPtr<DOMException> take(ScriptPromiseResolver*, WebType* webErrorRaw);
+    static DOMException* take(ScriptPromiseResolver*, WebType* webErrorRaw);
     static void dispose(WebType* webErrorRaw);
 
 private: