Remove a few unnecessary includes to speed up compiles.


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665673 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/cpp/src/transport/THttpClient.cpp b/lib/cpp/src/transport/THttpClient.cpp
index 901a4e0..a294093 100644
--- a/lib/cpp/src/transport/THttpClient.cpp
+++ b/lib/cpp/src/transport/THttpClient.cpp
@@ -5,6 +5,7 @@
 // http://developers.facebook.com/thrift/
 
 #include <cstdlib>
+#include <sstream>
 
 #include "THttpClient.h"
 #include "TSocket.h"