Fix remote_adb_setup with new `pub run sky_tools run_mojo` command.

mojo/devtools/common/remote_adb_setup

Index: mojo/devtools/common/remote_adb_setup
diff --git a/mojo/devtools/common/remote_adb_setup b/mojo/devtools/common/remote_adb_setup
index df3176d372e521d243fb4c11cc01f85c986a829d..aa67d6f0fec04d67d9677e85705a3cdd5d98a21c 100755
--- a/mojo/devtools/common/remote_adb_setup
+++ b/mojo/devtools/common/remote_adb_setup
@@ -43,11 +43,13 @@ adb start-server
 #   5037: adb
 # and from the local host to the remote host:
 #   9998: http server for Sky
-#   31840: http server for the local mojo: origin
 #   31839: http server for https://core.mojoapps.io
+#   31840: http server for the local mojo: origin
+#   31841: http server for base mappings
 ssh -C \
     -R 5037:127.0.0.1:5037 \
     -L 9998:127.0.0.1:9998 \
     -L 31839:127.0.0.1:31839 \
     -L 31840:127.0.0.1:31840 \
+    -L 31841:127.0.0.1:31841 \
     "$remote_host"