stream: Fixes missing 'unpipe' event

Currently when the destination emits an 'error', 'finish' or 'close'
event the pipe calls unpipe to emit 'unpipe' and trigger the clean up
of all it's listeners.
When the source emits an 'end' event without {end: false} it calls
end() on the destination leading it to emit a 'close', this will again
lead to the pipe calling unpipe. However the source emitting an 'end'
event along side {end: false} is the only time the cleanup gets ran
directly without unpipe being called. This fixes that so the 'unpipe'
event does get emitted and cleanup in turn gets ran by that event.

Fixes: https://github.com/nodejs/node/issues/11837
PR-URL: https://github.com/nodejs/node/pull/11876


Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>