These methods don't act like anything people would be familiar with (new Ctor(...), more specifically). They're only used by E4X internals in all of Mozilla. We should remove them.
I sent a query out to the newgroup to see if anyone's using these, and if so how to address any use case they might have (however awkwardly) been fulfilling:
Created attachment 627066 [details] [diff] [review]
Some people are using these APIs, and I'm still working through trying to migrate them to something better (probably JS_New for the most part). Just posting this to get it in the database for now...
Created attachment 628783 [details] [diff] [review]
One response in the newsgroups we determined could be worked through with JS_New. The other response mentioned they used the methods but never responded to my response asking if JS_New wouldn't work to address them. So going by that, one embedder has a reasonable workaround, and another hasn't said he doesn't.
At some point you have to move forward, so let's put this up for review now. (I sent one last newsgroup ping noting I was putting the patch up for review, for anyone who missed the earlier bits of the thread.)
I marked these methods as obsolete:
I also noted these methods' removal in release notes: