Created attachment 578784 [details] [diff] [review] patch We can use the datatransfer for what it needs.
Comment on attachment 578784 [details] [diff] [review] patch >+ dragEvent->dataTransfer->GetDropEffectInt(&action); nsIDOMDataTransfer has no method named GetDropEffectInt yet. r=me with that fixed. >+ // True while dragging over the tree. >+ bool mIsDragging; This belongs with mDropAllowed (for packing).