WL-3191 Only count READ roles

When determining which roles are defined for role-based access, only
consider those that grant READ access.

This exists because it is possible to define a role which doesn't grant
read access but will still consider this as role-based access.

This currently blocks adding role-based access and removing it.

kernel-impl/src/main/java/org/sakaiproject/content/impl/BaseContentService.java

@@ -9138,7 +9138,9 @@ public Set<String> getRoleViews(final String id) {
 
 		Set<Role> roles = realm.getRoles();
 		for (Role role : roles) {
-			roleIds.add(role.getId());
+			if(role.isAllowed(AUTH_RESOURCE_READ)) {
+				roleIds.add(role.getId());
+			}
 		}
 
 		return roleIds;