dart web : couldn't run webdev

I installed webdev to run dart web but when I want to run webdev it's showing an error:

Building package executable... 
Failed to build webdev:webdev:
../../.pub-cache/hosted/pub.dartlang.org/dds-2.1.6/lib/src/cpu_samples_manager.dart:54:21: Error: Type 'CpuSamplesEvent' not found.
  void cacheSamples(CpuSamplesEvent samples) {
                    ^^^^^^^^^^^^^^^
../../.pub-cache/hosted/pub.dartlang.org/dds-2.1.6/lib/src/cpu_samples_manager.dart:54:21: Error: 'CpuSamplesEvent' isn't a type.
  void cacheSamples(CpuSamplesEvent samples) {
                    ^^^^^^^^^^^^^^^

How can I fix it?

I just fixed that.

I edited cpu_samples_manager.dart in ~/.pub-cache/hosted/pub.dartlang.org/dds-2.1.6/lib/src/ and replace CpuSamplesEvent with var. ;)

anyway, if there is a better solution, please let me know.