THRIFT-2352 msvc failed to compile thrift tests

Patch: Sergei Nikulov & Roger Meier
diff --git a/lib/cpp/test/JSONProtoTest.cpp b/lib/cpp/test/JSONProtoTest.cpp
index be8f426..a3259c0 100644
--- a/lib/cpp/test/JSONProtoTest.cpp
+++ b/lib/cpp/test/JSONProtoTest.cpp
@@ -134,7 +134,7 @@
   dub.neginf = -HUGE_VAL;
   dub.repeating = 10.0/3.0;
   dub.big = 1E+305;
-  dub.small = 1E-305;
+  dub.tiny = 1E-305;
   dub.zero = 0.0;
   dub.negzero = -0.0;
   cout << apache::thrift::ThriftJSONString(dub) << endl << endl;