Hid test-only functions from surface/call.h
diff --git a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
index 7be3c9e..01e0d8d 100644
--- a/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
+++ b/vsprojects/vcxproj/grpc_unsecure/grpc_unsecure.vcxproj.filters
@@ -641,6 +641,9 @@
     <ClInclude Include="..\..\..\src\core\surface\call.h">
       <Filter>src\core\surface</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\..\src\core\surface\call_test_only.h">
+      <Filter>src\core\surface</Filter>
+    </ClInclude>
     <ClInclude Include="..\..\..\src\core\surface\channel.h">
       <Filter>src\core\surface</Filter>
     </ClInclude>