network: randomise the order of address subscriptions

Before this, we were subscribing to our addresses in their bip32 order,
leaking this information to servers. While this leak seems mostly harmless,
it is trivial to fix.

electrum/lnworker.py

@@ -35,7 +35,7 @@ from .crypto import sha256
 from .bip32 import BIP32Node
 from .util import bh2u, bfh, InvoiceError, resolve_dns_srv, is_ip_address, log_exceptions
 from .util import ignore_exceptions, make_aiohttp_session, SilentTaskGroup
-from .util import timestamp_to_datetime
+from .util import timestamp_to_datetime, random_shuffled_copy
 from .util import MyEncoder
 from .logging import Logger
 from .lntransport import LNTransport, LNResponderTransport
@@ -499,7 +499,7 @@ class LNWallet(LNWorker):
         # note: accessing channels (besides simple lookup) needs self.lock!
         self._channels = {}  # type: Dict[bytes, Channel]
         channels = self.db.get_dict("channels")
-        for channel_id, c in channels.items():
+        for channel_id, c in random_shuffled_copy(channels.items()):
             self._channels[bfh(channel_id)] = Channel(c, sweep_address=self.sweep_address, lnworker=self)
 
         self.pending_payments = defaultdict(asyncio.Future)  # type: Dict[bytes, asyncio.Future[BarePaymentAttemptLog]]
@@ -1397,7 +1397,7 @@ class LNBackups(Logger):
         self.wallet = wallet
         self.db = wallet.db
         self.channel_backups = {}
-        for channel_id, cb in self.db.get_dict("channel_backups").items():
+        for channel_id, cb in random_shuffled_copy(self.db.get_dict("channel_backups").items()):
             self.channel_backups[bfh(channel_id)] = ChannelBackup(cb, sweep_address=self.sweep_address, lnworker=self)
 
     @property