Remove unnecessary StackTrace instantiation (dart-lang/json_rpc_2#69)

Manually instantiating `StackTrace.current` when completing with an
error does not create a meaningfully different stack trace compared to
not passing one at all - it has an extra frame but not a meaningful one.
2 files changed
tree: 1fa6e3035323f6272efc0c328e79c094c2c74b42
  1. pkgs/