fix reversion on repo deletion

A broken symlink would cause the mode setting to fail.

Assistant/WebApp/Configurators/Delete.hs

@@ -99,7 +99,8 @@ deleteCurrentRepository = dangerPage $ do
 			{- Make all directories writable and files writable
 			 - so all annexed content can be deleted. -}
 			liftIO $ do
-				recurseDir SystemFS dir >>= mapM_ allowWrite
+				recurseDir SystemFS dir
+					>>= mapM_ (void . tryIO . allowWrite)
 				removeDirectoryRecursive dir
 			
 			redirect ShutdownConfirmedR

Test.hs

@@ -1178,7 +1178,7 @@ cleanup' final dir = whenM (doesDirectoryExist dir) $ do
 	-- they can be deleted. Both git and git-annex use file
 	-- permissions to prevent deletion.
 	recurseDir SystemFS dir >>=
-		mapM_ Utility.FileMode.allowWrite
+		mapM_ (void . tryIO . Utility.FileMode.allowWrite)
 	-- This sometimes fails on Windows, due to some files
 	-- being still opened by a subprocess.
 	catchIO (removeDirectoryRecursive dir) $ \e -> do