Avoid eager copying with BytesBuilder (#186)
Avoid eager copying with BytesBuilder (#186)

The previous implementation of `collectBytes` would return a `Uint8List`
where the `lengthInBytes` and `buffer.lengthInBytes` matched. This
property isn't an intended guarantee, however since some callers may
rely on it for correct behavior it is safer to retain it. Use `copy: false`
so that the buffer used in `takeBytes` has the same length as the data.
dart-lang/async