update Makefile.am

Makefile.am

diff --git a/Makefile.am b/Makefile.am
index 5df0d53..755355f 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -82,12 +82,15 @@
   csharp/src/AddressBook/ListPeople.cs                                       \
   csharp/src/AddressBook/Program.cs                                          \
   csharp/src/AddressBook/SampleUsage.cs                                      \
-  csharp/src/Google.Protobuf.Benchmarks/SerializationConfig.cs               \
-  csharp/src/Google.Protobuf.Benchmarks/SerializationBenchmark.cs            \
-  csharp/src/Google.Protobuf.Benchmarks/Program.cs                           \
-  csharp/src/Google.Protobuf.Benchmarks/Google.Protobuf.Benchmarks.csproj    \
-  csharp/src/Google.Protobuf.Benchmarks/Benchmarks.cs                        \
   csharp/src/Google.Protobuf.Benchmarks/BenchmarkMessage1Proto3.cs           \
+  csharp/src/Google.Protobuf.Benchmarks/Benchmarks.cs                        \
+  csharp/src/Google.Protobuf.Benchmarks/Google.Protobuf.Benchmarks.csproj    \
+  csharp/src/Google.Protobuf.Benchmarks/Program.cs                           \
+  csharp/src/Google.Protobuf.Benchmarks/SerializationBenchmark.cs            \
+  csharp/src/Google.Protobuf.Benchmarks/SerializationConfig.cs               \
+  csharp/src/Google.Protobuf.Benchmarks/wrapper_benchmark_messages.proto     \
+  csharp/src/Google.Protobuf.Benchmarks/WrapperBenchmark.cs                  \
+  csharp/src/Google.Protobuf.Benchmarks/WrapperBenchmarkMessages.cs          \
   csharp/src/Google.Protobuf.Conformance/Conformance.cs                      \
   csharp/src/Google.Protobuf.Conformance/Google.Protobuf.Conformance.csproj  \
   csharp/src/Google.Protobuf.Conformance/Program.cs                          \