Implement an ErrorEvent constructor for V8

Implement an ErrorEvent constructor for V8
https://bugs.webkit.org/show_bug.cgi?id=68336

Patch by Kentaro Hara <haraken@chromium.org> on 2011-09-28
Reviewed by Adam Barth.

Source/WebCore:

Test: fast/events/constructors/error-event-constructor.html

* bindings/v8/OptionsObject.cpp:
(WebCore::OptionsObject::getKeyValue): Returns an unsigned value corresponding to a given key.
* bindings/v8/OptionsObject.h:
* bindings/v8/custom/V8EventConstructors.cpp: Added the ErrorEvent constructor.
* dom/ErrorEvent.idl: Added a 'V8CustomConstructor' attribute.

LayoutTests:

Enabled fast/events/constructors/error-event-constructor.html,
since V8 now has the constructor for ErrorEvent.

* platform/chromium/test_expectations.txt:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@96208 268f45cc-cd09-0410-ab3c-d52691b4dbfc