Implement as per spec. Hopefully with XBL/JS.
So after talking to bz about this on irc, it has been determined that this needs to be implemented in C++ because of issues with XBL. These may be fixed in XBL2. Essentially, the properties added by XBL aren't visible to C++ code accessing the DOM initially. This is why it had to be written in C++.
Created attachment 231868 [details] IDL Here's the IDL file for the element. Should save someone some time.
clarification: display:none breaks XBL bindings right now. :(
Created attachment 232473 [details] [diff] [review] v0.1 This isn't done, but it's progress (best that I have it in more that one place). This will compile with v0.2 on Bug 347007 assuming I got all the files for each patch. Feedback welcome.
Created attachment 234357 [details] [diff] [review] v0.2 Ignore the stuff about nsDOMRepetitionEvent as that code is related to Bug 347007. Some of this stuff works correctly, but I make no claims to functionality of things that say they don't work. If you want to provide feedback, by all means do so. :)
Created attachment 234834 [details] [diff] [review] v1.0 As per conversations with sicking on irc, I'm going to be breaking this up into much smaller bugs to try to help out the reviewers. This is just a subset of v0.2, but it's just the function headers and what is needed for the tearoff to work. This code does in fact work for the tearoff, but obviously none of the functions exist in this patch.
Er.... So what do you want review on? You can't land that part on its own...
Repetition has been dropped in HTML 5. Should this bug be marked as WONTFIX?