THRIFT-4730: remove pthread code and refactor, ending up with just ThreadFactory

diff --git a/lib/cpp/test/TransportTest.cpp b/lib/cpp/test/TransportTest.cpp
index ce19544..3872071 100644
--- a/lib/cpp/test/TransportTest.cpp
+++ b/lib/cpp/test/TransportTest.cpp
@@ -1031,7 +1031,7 @@
     apache::thrift::transport::TWinsockSingleton::create();
 #endif
 
-    apache::thrift::concurrency::PlatformThreadFactory factory;
+    apache::thrift::concurrency::ThreadFactory factory;
     factory.setDetached(false);
 
     alarmThread_ = factory.newThread(