Add tests for TLS fallback on connection reset and close.

third_party/tlslite/tlslite/tlsrecordlayer.py

Index: third_party/tlslite/tlslite/tlsrecordlayer.py
diff --git a/third_party/tlslite/tlslite/tlsrecordlayer.py b/third_party/tlslite/tlslite/tlsrecordlayer.py
index 370dc9a726ac4e038ee07f36901aa04fce00c10b..23c2a2f4d972751a3e80c8fad3492bf4d927fea3 100644
--- a/third_party/tlslite/tlslite/tlsrecordlayer.py
+++ b/third_party/tlslite/tlslite/tlsrecordlayer.py
@@ -19,6 +19,7 @@ from .constants import *
 from .utils.cryptomath import getRandomBytes
 
 import socket
+import struct
 import errno
 import traceback
 
@@ -523,6 +524,13 @@ class TLSRecordLayer(object):
         self._shutdown(False)
         raise TLSLocalAlert(alert, errorStr)
 
+    def _abruptClose(self, reset=False):
+        if reset:
+            #Set an SO_LINGER timeout of 0 to send a TCP RST.
+            self.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER,
+                            struct.pack('ii', 1, 0))
+        self._shutdown(False)
+
     def _sendMsgs(self, msgs):
         randomizeFirstBlock = True
         for msg in msgs: