NOTE: This was fixed with both #53775 and #53715, if cherry-picking the fix include both.
I suspect this is because we use a regex on git tags in the flutter tool to detect tagged releases, which the new tag does not match.
~/git/flutter$ flutter doctor -v
[✓] Flutter (Channel master, v1.16.4-pre.46, on Mac OS X 10.15.3 19D76, locale en-US)
• Flutter version 1.16.4-pre.46 at /Users/fujino/git/flutter
• Framework revision 730a440fd5 (12 minutes ago), 2020-03-31 16:26:01 -0400
• Engine revision 6b09714a2c
• Dart version 2.8.0 (build 2.8.0-dev.18.0 11d6bc6055)
~/git/flutter$ git tag | grep 'dev'
1.17.0-dev.0.0
UPDATE: The problem code is:
return parse(_runGit('git describe --match v*.*.* --first-parent --long --tags', processUtils, workingDirectory));