Oilpan: have DOMException be on the heap by default.

Source/modules/fetch/Body.h

Index: Source/modules/fetch/Body.h
diff --git a/Source/modules/fetch/Body.h b/Source/modules/fetch/Body.h
index 67af33e0a244fffadfcba8290fc22447993b4a21..6a9435d7bf9c4ea313fb574ab3d1aac6590aa943 100644
--- a/Source/modules/fetch/Body.h
+++ b/Source/modules/fetch/Body.h
@@ -21,6 +21,7 @@ namespace blink {
 
 class BodyStreamBuffer;
 class BodyStreamSource;
+class DOMException;
 class ReadableByteStream;
 class ScriptState;
 
@@ -102,7 +103,7 @@ private:
     virtual void didFinishLoading() override;
     virtual void didFail(FileError::ErrorCode) override;
 
-    void didBlobHandleReceiveError(PassRefPtrWillBeRawPtr<DOMException>);
+    void didBlobHandleReceiveError(DOMException*);
 
     // We use BlobDataHandle or BodyStreamBuffer as data container of the Body.
     // BodyStreamBuffer is used only when the Response object is created by