new BUG-87 - faces with empty locn and no formal connection between file and face? Quick hack added to files as well to at least prevent a 500 server fault, and show it to us if it happens again

files.py

@@ -723,7 +723,15 @@ def view(id):
             continue
         # put locn data back into array format 
         for face in e.file_details.faces:
-            face.locn = json.loads(face.locn)
+            if face.locn:
+                face.locn = json.loads(face.locn)
+            else:
+				# this at least stops a 500 server error - seems to occur when
+				# DB contains disconnected faces with no locn data - BUG: 87
+                face.locn = [ 0,0,0,0 ]
+                st.SetMessage( f"For some reason this face does not have a locn: face_id={face.id} tell ddp", "warning" )
+
+
 
     eids=eids.rstrip(",")
     # jic, sometimes we trip this, and rather than show broken pages / destroy