fix encryption of content to gcrypt and git-lfs

Fix serious regression in gcrypt and encrypted git-lfs remotes.
Since version 7.20200202.7, git-annex incorrectly stored content
on those remotes without encrypting it.

Problem was, Remote.Git enumerates all git remotes, including git-lfs
and gcrypt. It then dispatches to those. So, Remote.List used the
RemoteConfigParser from Remote.Git, instead of from git-lfs or gcrypt,
and that parser does not know about encryption fields, so did not
include them in the ParsedRemoteConfig. (Also didn't include other
fields specific to those remotes, perhaps chunking etc also didn't
get through.)

To fix, had to move RemoteConfig parsing down into the generate methods
of each remote, rather than doing it in Remote.List.

And a consequence of that was that ParsedRemoteConfig had to change to
include the RemoteConfig that got parsed, so that testremote can
generate a new remote based on an existing remote.

(I would have rather fixed this just inside Remote.Git, but that was not
practical, at least not w/o re-doing work that Remote.List already did.
Big ugly mostly mechanical patch seemed preferable to making git-annex
slower.)

Remote/Helper/ExportImport.hs

@@ -72,15 +72,11 @@ importIsSupported = \_ _ -> return True
 -- | Prevent or allow exporttree=yes and importtree=yes when
 -- setting up a new remote, depending on exportSupported and importSupported.
 adjustExportImportRemoteType :: RemoteType -> RemoteType
-adjustExportImportRemoteType rt = rt
-	{ setup = setup'
-	, configParser = configparser
-	}
+adjustExportImportRemoteType rt = rt { setup = setup' }
   where
-	configparser c = addRemoteConfigParser exportImportConfigParsers 
-		<$> configParser rt c
 	setup' st mu cp c gc = do
-		pc <- either giveup return . parseRemoteConfig c =<< configparser c
+		pc <- either giveup return . parseRemoteConfig c
+			=<< configParser rt c
 		let checkconfig supported configured configfield cont =
 			ifM (supported rt pc gc)
 				( case st of
@@ -89,7 +85,7 @@ adjustExportImportRemoteType rt = rt
 							giveup $ "cannot enable both encryption and " ++ fromProposedAccepted configfield
 						| otherwise -> cont
 					Enable oldc -> do
-						oldpc <- either mempty id . parseRemoteConfig oldc <$> configparser oldc
+						oldpc <- parsedRemoteConfig rt oldc
 						if configured pc /= configured oldpc
 							then giveup $ "cannot change " ++ fromProposedAccepted configfield ++ " of existing special remote"
 							else cont
@@ -103,14 +99,6 @@ adjustExportImportRemoteType rt = rt
 					then giveup "cannot enable importtree=yes without also enabling exporttree=yes"
 					else setup rt st mu cp c gc
 
-exportImportConfigParsers :: [RemoteConfigFieldParser]
-exportImportConfigParsers =
-	[ yesNoParser exportTreeField False
-		(FieldDesc "export trees of files to this remote")
-	, yesNoParser importTreeField False
-		(FieldDesc "import trees of files from this remote")
-	]
-
 -- | Adjust a remote to support exporttree=yes and importree=yes.
 --
 -- Note that all remotes with importree=yes also have exporttree=yes.