wallet, test: Be able to always swap BDB endianness

test/functional/tool_wallet.py

@@ -24,11 +24,14 @@ class ToolWalletTest(BitcoinTestFramework):
     def add_options(self, parser):
         self.add_wallet_options(parser)
         parser.add_argument("--bdbro", action="store_true", help="Use the BerkeleyRO internal parser when dumping a Berkeley DB wallet file")
+        parser.add_argument("--swap-bdb-endian", action="store_true",help="When making Legacy BDB wallets, always make then byte swapped internally")
 
     def set_test_params(self):
         self.num_nodes = 1
         self.setup_clean_chain = True
         self.rpc_timeout = 120
+        if self.options.swap_bdb_endian:
+            self.extra_args = [["-swapbdbendian"]]
 
     def skip_test_if_missing_module(self):
         self.skip_if_no_wallet()