Migrate to create_api_docs.dart

[srawlins]

Fixes #3481

[srawlins]

CC @gspencergoog I'm having trouble migrating to create_api_docs.dart. I tried following the updates made to docs.sh in flutter/flutter@ced3e76, but I'm still getting:

pub:stdout: Resolving dependencies...
pub:stderr: Because Flutter depends on flutter_test from sdk which doesn't exist (the Flutter SDK is not available), version solving failed.
pub:stderr:
pub:stderr: Flutter users should run `flutter pub get` instead of `dart pub get`.

This is being printed by the runPubProcess command at line 450 in create_api_docs.dart. Any ideas?

[gspencergoog]

Looking at this. I think I may have switched to running dart pub get in some places instead of flutter pub get.

[gspencergoog]

So, can you try out the changes in flutter/flutter#133493 ? I modified it to call flutter pub instead of dart pub, so the Flutter SDK should be available then.

[srawlins]

Thanks a million, Greg! I think I can test locally against your PR (maybe?) but I'll wait till it lands to land this change.

[gspencergoog]

Okay, cool. Would you be willing to review that change, or should I find someone else?

[srawlins]

Looks good Greg!