Fixed an infinite loop in plat_other when using a relative path in a mounted directory.

--HG--
branch : py3k
extra : transplant_source : %B4%A2%DB%EFn%BB%3A%F6%AE%06%F3%29%DB%06%FBE%D0%A2%BEt

send2trash/plat_other.py

@@ -33,8 +33,9 @@ EXTERNAL_CANDIDATES = [
 
 def find_mount_point(path):
     # Even if something's wrong, "/" is a mount point, so the loop will exit.
+    path = op.abspath(path) # Required to avoid infinite loop
     while not op.ismount(path):
-        path = op.join(*op.split(path)[:-1])
+        path = op.split(path)[0]
     return path
 
 def find_ext_volume_trash(volume_root):