SLING-3088 : handle one more case of 'can only set resource once' - namely when the resource is equals
SLING-3631 : fixing NPE when changing primary type in the normal properties view - plus changing the actual value of that property in the view

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1599594 13f79535-47bb-0310-9956-ffa450edef68