Speed up net_unittests by re-using one FTP test server instance.

third_party/pyftpdlib/google.patch

Index: third_party/pyftpdlib/google.patch
diff --git a/third_party/pyftpdlib/google.patch b/third_party/pyftpdlib/google.patch
new file mode 100644
index 0000000000000000000000000000000000000000..43a74c2b08502e059daf3c2f2c85902b861279a2
--- /dev/null
+++ b/third_party/pyftpdlib/google.patch
@@ -0,0 +1,23 @@
+--- pyftpdlib/ftpserver.py
++++ pyftpdlib/ftpserver.py
+@@ -2546,14 +2546,12 @@ class FTPHandler(asynchat.async_chat):
+                 self.fs.root = self.authorizer.get_home_dir(self.username)
+                 self.log("User %s logged in." %self.username)
+             else:
+-                CallLater(5, auth_failed)
++                auth_failed()
+                 self.username = ""
+-                self.sleeping = True
+         # wrong username
+         else:
+             if self.username.lower() == 'anonymous':
+-                CallLater(5, auth_failed, "Anonymous access not allowed.")
++                auth_failed("Anonymous access not allowed.")
+             else:
+-                CallLater(5, auth_failed)
++                auth_failed()
+             self.username = ""
+-            self.sleeping = True
+
+     def ftp_REIN(self, line):
+         """Reinitialize user's current session."""