Small changes in documentation of the empty message tests.

test/proto/empty_message.proto

@@ -28,7 +28,7 @@
  *    the Netherlands
  */
 
-// This file is used to test serializing repeated fields.
+// This file is used to test defining empty messages. This should not cause build errors.
 
 syntax = "proto3";
 

test/test_empty_messages.cpp

@@ -37,7 +37,8 @@ namespace test_EmbeddedAMS_empty_messages
 {
 
 TEST(EmptyMessages, construction)
-{
+{ 
+  // Test if using a message with no fields or enums cause build errors. 
   empty_message empty;
 }