spirv-fuzz: fix test (#3845)

Fix test that broke due to a merge.
diff --git a/test/fuzz/transformation_add_synonym_test.cpp b/test/fuzz/transformation_add_synonym_test.cpp
index 3b49ee6..fba93fb 100644
--- a/test/fuzz/transformation_add_synonym_test.cpp
+++ b/test/fuzz/transformation_add_synonym_test.cpp
@@ -1436,12 +1436,11 @@
   const auto consumer = nullptr;
   const auto context = BuildModule(env, consumer, shader, kFuzzAssembleOption);
 
-  FactManager fact_manager(context.get());
   spvtools::ValidatorOptions validator_options;
-  TransformationContext transformation_context(&fact_manager,
-                                               validator_options);
+  TransformationContext transformation_context(
+      MakeUnique<FactManager>(context.get()), validator_options);
 
-  fact_manager.AddFactBlockIsDead(9);
+  transformation_context.GetFactManager()->AddFactBlockIsDead(9);
 
   auto insert_before = MakeInstructionDescriptor(9, SpvOpBranch, 0);