message: Fix error caused by using the deleted copy constructor for mock.
diff: @@ -189,7 +189,7 @@ std::unique_ptr<OutputPrimitive> GetOutputPrimitiveForTesting() {
  // Tests that annotations are correctly passed on to the generated PrimitiveSet.
  TEST(KeysetWrapperImplTest, WrapWithAnnotationCorrectlyWrittenToPrimitiveSet) {
  - auto wrapper = MockWrapper<InputPrimitive, OutputPrimitive>();
  + MockWrapper<InputPrimitive, OutputPrimitive> wrapper;
  auto keyset_wrapper =
  absl::make_unique<KeysetWrapperImpl<InputPrimitive, OutputPrimitive>>(
  &wrapper, CreateIn);
  