When a plugin has an activation error, it was not being checked in the
`waitActive` loop. This means it will just wait forever for a manifest
to be populated even though it may never come.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
(cherry picked from commit f2d384fca6)
Signed-off-by: Victor Vieux <vieux@docker.com>