Add unittest.

code/Common/PostStepRegistry.cpp

@@ -131,6 +131,10 @@ corresponding preprocessor flag to selectively disable steps.
 #if (!defined ASSIMP_BUILD_NO_GLOBALSCALE_PROCESS)
 #   include "PostProcessing/ScaleProcess.h"
 #endif
+#if (!defined ASSIMP_BUILD_NO_GENBOUNDINGBOXES_PROCESS)
+#   include "PostProcessing/GenBoundingBoxesProcess.h"
+#endif
+
 
 namespace Assimp {
 
@@ -246,6 +250,9 @@ void GetPostProcessingStepInstanceList(std::vector< BaseProcess* >& out)
 #if (!defined ASSIMP_BUILD_NO_IMPROVECACHELOCALITY_PROCESS)
     out.push_back( new ImproveCacheLocalityProcess());
 #endif
+#if (!defined ASSIMP_BUILD_NO_GENBOUNDINGBOXES_PROCESS)
+    out.push_back(new GenBoundingBoxesProcess);
+#endif
 }
 
 }