NPE when accessing file in Dropbox

Regression from KNL-1514 where isDropboxMaintainer() looks at Threadlocal to get the current placement but there is no binding for "sakai:ToolComponent:current.placement" when using access. Could look at why there is no placement for access but there is a similar method where the siteid can be used isDropboxMaintainer(String siteId). In this case opting to use latter as the siteid is known.