[SDK] Ensure compatibility between frontend_server AOT snapshot and dartaotruntime in release builds

Change-Id: I7d0e98de681268afc71349a9c7a8efeaf2f4e019
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/323241
Reviewed-by: Ben Konyi <bkonyi@google.com>

utils/kernel-service/BUILD.gn

@@ -67,6 +67,13 @@ aot_snapshot("frontend_server_aot") {
   main_dart = "../../pkg/frontend_server/bin/frontend_server_starter.dart"
   name = "frontend_server_aot"
   output = "$root_out_dir/frontend_server_aot.dart.snapshot"
+
+  # dartaotruntime has dart_product_config applied to it, so it is built in
+  # product mode in both release and product builds, and is only built in debug
+  # mode in debug builds. The following line ensures that the dartaotruntime and
+  # frontend_server_aot snapshot in an SDK build are always compatible with
+  # each other.
+  force_product_mode = !dart_debug
 }
 
 template("kernel_service_dill") {