If a user had a capability added by a plugin, e.g. in case of the
serviceuser plugin to create a service user, but was not an
administrator, modifying a resource was failing. The error involved was:
com.google.gerrit.server.permissions.PermissionBackendException:
cannot extract permission
This error was caused, since the plugin name was not set in the viewData,
when the capabilities were checked in case the view was
a child RestCollection.
This change sets the plugin name in the viewData to the value of the
parent view instead of setting it to `null`.
Bug: Issue 11374
Change-Id: Ia679367216cf8898b60445a1290b9ac5b1f56b25
dbbe888f5f