Don't include FactoryHelper.hpp more than once

Summary:
FactoryHelper.hpp is expensive, with generated code for DataLayout. We should not include it more than strictly necessary.
This diff removes unwarranted includes and adds fake function to break linking if it's included more than once.

Reviewed By: finik

Differential Revision: D74044527

fbshipit-source-id: 1f6a7a20a51f0f9ad6a72fda12da77d341030c9a

Author: Georges Berenger

csrc/reader/FactoryHelper.hpp

@@ -181,3 +181,11 @@ DEFINE_DATA_PIECE(Vector, string)
 DEFINE_DATA_PIECE(StringMap, string)
 
 } // namespace
+
+namespace pyvrs {
+// To prevent the inclusion of this expensive header in more than one file, this function should
+// trigger a linker error if included more than once
+int singleIncludeBreakCheck() {
+  return 0;
+}
+} // namespace pyvrs

csrc/reader/MultiVRSReader.cpp

@@ -45,7 +45,6 @@
 #include "../utils/PyExceptions.h"
 #include "../utils/PyRecord.h"
 #include "../utils/PyUtils.h"
-#include "FactoryHelper.hpp"
 
 using UniqueStreamId = vrs::MultiRecordFileReader::UniqueStreamId;