Fix warning about unused variable in unit test
diff --git a/src/google/protobuf/compiler/java/java_plugin_unittest.cc b/src/google/protobuf/compiler/java/java_plugin_unittest.cc
index 0d4ea16..f7f3cf9 100644
--- a/src/google/protobuf/compiler/java/java_plugin_unittest.cc
+++ b/src/google/protobuf/compiler/java/java_plugin_unittest.cc
@@ -126,6 +126,7 @@
     }
   }
   EXPECT_TRUE(found_do_not_edit);
+  (void)found_generated_annotation;
 }
 
 }  // namespace