Fix onunload test case
Fix onunload test case

- the previous test only remove last item on array, but expect all
subcomponent's onunload to be called. This PR change it by clear that
array.
- uncomment previous test case that marked fail.

barneycarroll/mithril.js,MithrilJS/mithril.js,impinball/mithril.js,lhorie/mithril.js,mrvicadai/mithril.js,MithrilJS/mithril.js,barneycarroll/mithril.js,maxlang/mithril.js,lhorie/mithril.js,tivac/mithril.js,maxlang/mithril.js,impinball/mithril.js,mrvicadai/mithril.js,pygy/mithril.js,pygy/mithril.js,tivac/mithril.js