refactor git-annex branch log filename code into central location

Having one module that knows about all the filenames used on the branch
allows working back from an arbitrary filename to enough information about
it to implement dropping dead remotes and doing other log file compacting
as part of a forget transition.

Upgrade/V2.hs

@@ -12,9 +12,9 @@ import qualified Git
 import qualified Git.Command
 import qualified Git.Ref
 import qualified Annex.Branch
-import Logs.Location
 import Annex.Content
 import Utility.Tmp
+import Logs
 
 olddir :: Git.Repo -> FilePath
 olddir g
@@ -47,7 +47,7 @@ upgrade = do
 
 	e <- liftIO $ doesDirectoryExist old
 	when e $ do
-		mapM_ (\(k, f) -> inject f $ logFile k) =<< locationLogs
+		mapM_ (\(k, f) -> inject f $ locationLogFile k) =<< locationLogs
 		mapM_ (\f -> inject f f) =<< logFiles old
 
 	saveState False
@@ -73,7 +73,7 @@ locationLogs = do
   where
 	tryDirContents d = catchDefaultIO [] $ dirContents d
 	islogfile f = maybe Nothing (\k -> Just (k, f)) $
-			logFileKey $ takeFileName f
+			locationLogFileKey f
 
 inject :: FilePath -> FilePath -> Annex ()
 inject source dest = do