Color deprecations should have a dart fix

[Piinks]

Deprecations from flutter/engine#54737 should have a dart fix.

I noticed user-created content out in the wild trying to help folks migrate:

Dart fix has not been enabled for dart:ui and others, following up in dart-lang/sdk#59764

WIP PR to add this support in #160616

For reference, the migration guide: https://docs.flutter.dev/release/breaking-changes/wide-gamut-framework

[gaaclarke]

I already added dart fix for .opacity .withOpacity: #154953

[max-anders]

I already added dart fix for .opacity .withOpacity: #154953

Hello, is the fix coming to the Flutter stable channel ? dart fix --apply is not doing it for me.