Add client for background testing of HTTP pipelining.

net/tools/testserver/testserver.py

Index: net/tools/testserver/testserver.py
diff --git a/net/tools/testserver/testserver.py b/net/tools/testserver/testserver.py
index f9177897cc6e17b64a3fa075498365b96f0a7b81..88daaa11fac8542ddf29e45714170f723a7deb06 100755
--- a/net/tools/testserver/testserver.py
+++ b/net/tools/testserver/testserver.py
@@ -378,6 +378,7 @@ class TestPageHandler(BasePageHandler):
       self.MultipartHandler,
       self.MultipartSlowHandler,
       self.GetSSLSessionCacheHandler,
+      self.CloseSocketHandler,
       self.DefaultResponseHandler]
     post_handlers = [
       self.EchoTitleHandler,
@@ -1427,6 +1428,15 @@ class TestPageHandler(BasePageHandler):
                        ' this request')
     return True
 
+  def CloseSocketHandler(self):
+    """Closes the socket without sending anything."""
+
+    if not self._ShouldHandleRequest('/close-socket'):
+      return False
+
+    self.wfile.close()
+    return True
+
   def DefaultResponseHandler(self):
     """This is the catch-all response handler for requests that aren't handled
     by one of the special handlers above.