Engine run configuration was invalid. I had same problem when I was back to stable channel that used an old engine respect to master channel.
Try to use master channel:
1 2 | flutter channel master flutter upgrade |
If you like this question & answer and want to contribute, then write your question & answer and email to freewebmentor[@]gmail.com. Your question and answer will appear on FreeWebMentor.com and help other developers.