dart analyzer doesn't invalidate .dartServer cache

[aam]

dart->flutter roller failed once https://github.com/flutter/flutter/pull/179502, then succeeded on the next roll seemingly without any actual fixes landing.

When troubleshooting this locally, I saw reported analyzer finding

/p/f/f1/flutter/packages/flutter  $ ~/p/f/f1/flutter/bin/flutter analyze  
Analyzing flutter...                                                    

warning • A value for optional parameter 'name' isn't ever given • lib/src/widgets/widget_inspector.dart:1:1 • unused_element_parameter

which only disappeared after I removed ~/.dartServer (moved it so I can restore it later).

The error came back after I restored ~/.dartServer.

This seems to point out to some change that landed in dart sdk https://dart.googlesource.com/sdk.git/+log/42fe3327abca..34287942e687

2025-12-05 [[email protected]](mailto:[email protected]) Version 3.11.0-210.0.dev
2025-12-04 [[email protected]](mailto:[email protected]) Version 3.11.0-209.0.dev

that didn't have provisions to invalidate analysis server cache properly.

cc @stereotype441 @scheglov