594340 - "Internet Explorer 9 Test Drive" stops. Error: Could not convert JavaScript argument = NS_ERROR_XPC_BAD_CONVERT_JS

Status: RESOLVED DUPLICATE of bug 560072

(Core :: JavaScript Engine, defect)

Description

[Alice0775 White]

Build Identifier:  Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b6pre) Gecko/20100907 Firefox/4.0b6pre ID:20100907041859

"Internet Explorer 9 Test Drive" stops.

Error: Could not convert JavaScript argument = NS_ERROR_XPC_BAD_CONVERT_JS
Source file: http://ie.microsoft.com/testdrive/HTML5/DOMCapabilities/demo.js
Line: 197

Reproducible: Always

Steps to Reproduce:
Open http://ie.microsoft.com/testdrive/HTML5/DOMCapabilities/Default.html

Comment 1

[Boris Zbarsky [:bzbarsky]]

backupTagNamePropDesc = Object.getOwnPropertyDescriptor(Element.prototype, "tagName");

is the relevant line.  Pretty sure we have a bug on this already...

Comment 2

[David Mandelin [:dmandelin]]

It looks similar to bug 520882, but I'm not sure if it's the same.

Comment 3

[Boris Zbarsky [:bzbarsky]]

I was thinking one of the ietestcenter bugs, but not finding it at the moment.

Comment 4

[Jeff Walden [:Waldo]]

Either bug 520882 or bug 560072, I think, depending how you read them -- but definitely a duplicate of the latter, so I'll dup to there and let someone else sort out whether bug 560072 should itself be a duplicate of bug 520882.  :-)