It returns whatever happens to be the first view child of the inner view. If there are two views (like during navigation between pages) we miss one. All existing users of this seem like this would be the correct thing to do. But my motivation is in the next patch posted in another bug.
(In reply to Timothy Nikkel (:tnikkel) from comment #0) > All existing users of this seem like this would be the correct thing to do. > But my motivation is in the next patch posted in another bug. "another bug" is bug 1261763.
Created attachment 8737708 [details] [diff] [review] patch I don't feel super great about letting there be more than one list with the id kSubDocumentList in the same array of ChildLists, but I couldn't figure out any better way to do it because each frame list has to be a true frame list that is linked to each other. The different subdocument root frames are not linked to each other.
Comment on attachment 8737708 [details] [diff] [review] patch This just feels very very wrong to me. Let's not mess with the meaning of child frame lists please. If we also have root views from previous navigations in BeginSwapDocShells let's just deal with that situation there (in bug 1261763).