Ok, this is definitely a blocker for turning on XBL form controls. From what I can tell, here's the problem: At the time that we construct an outlinerbodyframe, the binding for the outlinercols has not yet loaded, so we have not yet constructed a nsOutlinerColFrame. This causes outliner's intrinsic sizing to crash. Making the binding load synchronously turns out to be a fair bit of work, but something we may have to do anyway. In order for synchronous loading of the binding to work, we would need to sync load the resources (stylesheets) for the base binding. This would entail extending the CSS loader to support sync loading, and causing XBL to use this facility when you ask for a binding to be sync loaded (I think this would always be desired if you are sync loading the binding, hyatt correct me if I'm wrong). The CSS loader already supports sync loading of agent sheets, so this would just be a general extension of that mechanism (I don't think we awnt to actually load the binding stylesheets _as_ agent sheets). The other option would be to duplicate the outlinercols binding into select.xml so that it won't use scoped stylesheets. I'd prefer not to do this, as it means that the two copies wouldn't be able to share prototype bindings (hence a slight footprint hit). On the plus side, it would break the dependency on toolkit.jar; not sure this is all that important since we can already generate a minimal embed.jar.

One more note: the reason this doesn't happen in Mozilla is that the outlinercol binding can load synchronously from the XUL cache. nsbeta1+'ing since this will obviously block 112713.

A third way to fix this would be to make OutlinerBodyFrame able to function with its column frames constructed later; this seems like a bad idea all-around because it would generate extra reflows as the outliner resizes.

cc'ing jud since this affects embeddding

Well, there turns out to be an easy way to fix this...

Also fixing the forced sync loading of the select binding, which was probably never working right. This fixes the problem of mysterious missing select widgets.

Comment on attachment 72266 [details] [diff] [review] patch #2 looks good r=varga

Comment on attachment 72266 [details] [diff] [review] patch #2 sr=shaver.

Comment on attachment 72266 [details] [diff] [review] patch #2 a=roc+moz for trunk

Checked in on the trunk.

Verified patch checked into lxr.mozilla.org