Expected Behavior
Cancelling a PipelineRun should not succeed if the TaskRuns it created were not able to be cancelled.
Actual Behavior
In our PipelineRun cancellation code we immediately set the status of a PipelineRun to cancelled regardless of whether the TaskRuns it created were able to be cancelled.
This seems counter-intuitive and like a potential source of confusion for users. If TaskRuns couldn't be cancelled then that should probably be stored as some kind of error or event on the PipelineRun and the PipelineRun itself should remain in an un-cancelled state to indicate that there are still running processes related to it.