avoid sometimes expensive operations when annex.supportunlocked = false

This will mostly just avoid a DB lookup, so things get marginally
faster. But in cases where there are many files using the same key, it
can be a more significant speedup.

Added overhead is one MVar lookup per call, which should be small
enough, since this happens after transferring or ingesting a file,
which is always a lot more work than that. It would be nice, though,
to move getGitConfig to AnnexRead, which there is an open todo about.

Annex/Content.hs

@@ -340,12 +340,13 @@ moveAnnex key af src = ifM (checkSecureHashes' key)
 			liftIO $ moveFile
 				(fromRawFilePath src)
 				(fromRawFilePath dest)
-			g <- Annex.gitRepo 
-			fs <- map (`fromTopFilePath` g)
-				<$> Database.Keys.getAssociatedFiles key
-			unless (null fs) $ do
-				ics <- mapM (populatePointerFile (Restage True) key dest) fs
-				Database.Keys.storeInodeCaches' key [dest] (catMaybes ics)
+			whenM (annexSupportUnlocked <$> Annex.getGitConfig) $ do
+				g <- Annex.gitRepo 
+				fs <- map (`fromTopFilePath` g)
+					<$> Database.Keys.getAssociatedFiles key
+				unless (null fs) $ do
+					ics <- mapM (populatePointerFile (Restage True) key dest) fs
+					Database.Keys.storeInodeCaches' key [dest] (catMaybes ics)
 		)
 	alreadyhave = liftIO $ R.removeLink src
 
@@ -502,10 +503,11 @@ removeAnnex (ContentRemovalLock key) = withObjectLoc key $ \file ->
 	cleanObjectLoc key $ do
 		secureErase file
 		liftIO $ removeWhenExistsWith R.removeLink file
-		g <- Annex.gitRepo 
-		mapM_ (\f -> void $ tryIO $ resetpointer $ fromTopFilePath f g)
-			=<< Database.Keys.getAssociatedFiles key
-		Database.Keys.removeInodeCaches key
+		whenM (annexSupportUnlocked <$> Annex.getGitConfig) $ do
+			g <- Annex.gitRepo 
+			mapM_ (\f -> void $ tryIO $ resetpointer $ fromTopFilePath f g)
+				=<< Database.Keys.getAssociatedFiles key
+			Database.Keys.removeInodeCaches key
   where
 	-- Check associated pointer file for modifications, and reset if
 	-- it's unmodified.