Unfortunately, this behavior is common across all major browsers. There is a Chromium bug for it (http://crbug.com/315190), but no responses as of yet.
Unfortunately, you are right. I am optimistic, however.
IE used to not GC cyclical JS/DOM references. Google Chrome is doing a massive rework of DOM garbage collection with Oilpan.
You are right that it is not a trivial change, but there is nothing technically infeasible about GC'ing per closure. I think it is worth it, just as it was worth it for IE to have smarter GC.