compile_benchmarks.dart: Remove a redundant clone
compile_benchmarks.dart: Remove a redundant clone

dart-lang/protobuf,dart-lang/dart-protobuf,dart-lang/dart-protobuf,google/protobuf.dart,google/protobuf.dart,google/protobuf.dart,dart-lang/protobuf,dart-lang/dart-protobuf,dart-lang/protobuf