Update Error Event inside a worker to provide the exact exception value

third_party/WebKit/Source/core/events/ErrorEvent.h

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 30 matching lines @@
 
 namespace blink {
 
 class ErrorEvent final : public Event {
   DEFINE_WRAPPERTYPEINFO();
 
  public:
   static ErrorEvent* create() { return new ErrorEvent; }
   static ErrorEvent* create(const String& message,
                             std::unique_ptr<SourceLocation> location,
                             DOMWrapperWorld* world) {

[shimazu, 2017/04/05 07:23:22]

Just confirmation; do we still keep the old factory method?

[yiyix, 2017/04/05 09:02:56]

I can add a default value to |error|, where error is set to null. So it doesn't
break the existing functionalities. However, I noticed that the default value is
not used in most of service worker code, I want to know what other viewer think
about it.

[shimazu, 2017/04/05 09:29:40]

Yes, as you mentioned default values are not preferable. I just wanted to
confirm if there are other places using this method. Looks good as is.

     return new ErrorEvent(message, std::move(location), world);
   }
+
+  static ErrorEvent* create(const String& message,
+                            std::unique_ptr<SourceLocation> location,
+                            DOMWrapperWorld* world,
+                            ScriptValue error) {
+    ErrorEvent* event = new ErrorEvent(message, std::move(location), world);
+    event->m_error = error;
+    return event;
+  }
+
   static ErrorEvent* create(const AtomicString& type,
                             const ErrorEventInit& initializer) {
     return new ErrorEvent(type, initializer);
   }
   static ErrorEvent* createSanitizedError(DOMWrapperWorld* world) {
     return new ErrorEvent("Script error.",
                           SourceLocation::create(String(), 0, 0, nullptr),
                           world);
   }
   ~ErrorEvent() override;
@@ skipping 18 matching lines @@
   DOMWrapperWorld* world() const { return m_world.get(); }
 
   void setUnsanitizedMessage(const String&);
 
   DECLARE_VIRTUAL_TRACE();
 
  private:
   ErrorEvent();
   ErrorEvent(const String& message,
              std::unique_ptr<SourceLocation>,
              DOMWrapperWorld*);

[nhiroki, 2017/04/05 07:38:38]

How about changing this ctor as follows and then calling it from create(message,
location, world), create(message, location, error, world) and
createSanitizedError()?

ErrorEvent(const String& message, std::unique_ptr<SourceLocation>, ScriptValue
error, DOMWrapperWorld*);

[yiyix, 2017/04/05 09:02:56]

Done.

   ErrorEvent(const AtomicString&, const ErrorEventInit&);
 
   String m_unsanitizedMessage;
   String m_sanitizedMessage;
   std::unique_ptr<SourceLocation> m_location;
   ScriptValue m_error;
 
   RefPtr<DOMWrapperWorld> m_world;
 };
 
 }  // namespace blink
 
 #endif  // ErrorEvent_h