Fixes #1145. e.stopProp() edge case for focus

Multiple delegates for the same node were getting notified when e.stopProp()
was called, even though they were delegating from different containers. This
would be fine (delegate pretends to be individual direct subscriptions) if it
weren't inconsistent with how other events work in that scenario.
Merge branch 'focus-fix' into dev-3.x
Build event-focus