Enable miniFakeDns to take a port to bind to

Review URL: http://codereview.chromium.org/1729010
diff --git a/src/miniFakeDns.py b/src/miniFakeDns.py
index fbf742d..f1358d8 100755
--- a/src/miniFakeDns.py
+++ b/src/miniFakeDns.py
@@ -51,14 +51,15 @@
 class DNSServer:
   """A very, very simple DNS responder.
 
-  DNSServer will bind to port 53 on |server_address| and respond to any query
-  with an A record pointing to |fake_ip|.
+  DNSServer will bind to port |port| on |server_address| and respond
+  to any query with an A record pointing to |fake_ip|.
 
   Must be run with superuser privilege to bind to port 53
   """
-  def __init__(self, server_address='', fake_ip='192.168.1.1'):
+  def __init__(self, server_address='', fake_ip='192.168.1.1', port=53):
     self._udps = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
     self._address = server_address
+    self._port = port
     self._fake_ip = fake_ip
 
 
@@ -74,7 +75,8 @@
     .
     stopper.set()
     """
-    self._udps.bind((self._address, 53))
+    self._udps.bind((self._address, self._port))
+    print 'miniFakeDns listening on port %d' % self._port
     self._udps.settimeout(1)
     while not stop.is_set():
       try: