Oilpan: have DOMException be on the heap by default.

Source/modules/presentation/PresentationError.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "modules/presentation/PresentationError.h"
 
 #include "core/dom/DOMException.h"
 #include "core/dom/ExceptionCode.h"
 #include "public/platform/modules/presentation/WebPresentationError.h"
 #include "wtf/OwnPtr.h"
 
 namespace blink {
 
 // static
-PassRefPtrWillBeRawPtr<DOMException> PresentationError::take(WebPresentationError* errorRaw)
+DOMException* PresentationError::take(WebPresentationError* errorRaw)
 {
     ASSERT(errorRaw);
     OwnPtr<WebPresentationError> error = adoptPtr(errorRaw);
 
     // TODO(avayvod): figure out the mapping between WebPresentationError and
     // DOMException error codes.
     return DOMException::create(InvalidAccessError, error->message);
 }
 
 // static
 void PresentationError::dispose(WebPresentationError* error)
 {
     delete error;
 }
 
 } // namespace blink