Update mdc_web then roll those updates into DartPad

[parlough]

We currently have to override the sass dependency due to a previous issue with Material Components Web which the fix for has not yet rolled into package:mdc_web. Due to changes in modern sass versions, we also have to restrict sass_builder to an old version.

We should incorporate the new changes into package:mdc_web, then update the packages here and remove the necessary overrides.

[parlough]

@johnpryan Looks like holding back sass is going to start causing problems (https://github.com/dart-lang/dart-pad/actions/runs/3481346651/jobs/5822319108). I'm not familiar with the process of updating mdc_web or what is required there. Could you provide some context on how to do so or update it when you get a chance?

[johnpryan]

There's a script to automatically update the SASS in mdc_web: https://github.com/jifalops/mdc_web/blob/master/tool/generate_sass.dart.

Running that script will install (https://www.npmjs.com/package/material-components-web) version 14.0.0, and attempt to set up the SASS dependencies, but there's a few import issues when I try to run DartPad:

[SEVERE] sass_builder on lib/scss/material_shared.scss: Error: Undefined mixin.
   ╷
13 │   @include mdc-icon-button-size(14px);
   │   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   ╵
  - 13:3  root stylesheet

I'm not sure why this mixin isn't available - it probably just needs to be imported.

[johnpryan]

It looks like that mixin is deprecated, we'll need to figure out what the upgrade path looks like, but for now I'll try to remove any deprecated mixins and get DartPad building with material-components-web 14.0.0

[johnpryan]

For now, I was able to upgrade dart-sass and sass_builder to the latest version: #2537

[johnpryan]

I played around with package:mdc_web's generate_sass.dart script, to try different versions of the material-components-web NPM package.

  var result = await Process.run('npm', ['install', 'material-components-web@12.0.0']);

I tried 12.0.0, 13.0.0, and 14.0.0, but there are breaking changes that break mixins that dart-pad uses. Anywhere DartPad is using a mixin that starts with@include mdc-* is affected.

[parlough]

I'm going to close this as we aren't going to be using the package anymore, and the underlying web library has been superseded by a new, simplified component library anyway - https://material-web.dev/.