THRIFT-3579 Introduce retry to make cross

This closes #817
diff --git a/test/crossrunner/test.py b/test/crossrunner/test.py
index bb81c4f..fc90f7f 100644
--- a/test/crossrunner/test.py
+++ b/test/crossrunner/test.py
@@ -70,7 +70,7 @@
 
   def build_command(self, port):
     cmd = copy.copy(self._base_command)
-    args = self._extra_args2
+    args = copy.copy(self._extra_args2)
     args.append('--protocol=' + self.protocol)
     args.append('--transport=' + self.transport)
     socket_args = self._socket_args(self.socket, port)
@@ -109,6 +109,7 @@
     self.as_expected = None
     self.returncode = None
     self.expired = False
+    self.retry_count = 0
 
   def _fix_workdir(self, config):
     key = 'workdir'