Description

Adding optional argument to GoogleSignIn class to support a serverClientID string. This is required, for instance, to generate a user token to access a Google Cloud-IAP protected resource.

Example:

GoogleSignIn _googleSignIn = GoogleSignIn(
  serverClientID: "xxxxxxxxx.apps.googleusercontent.com", // OAuth Client ID of the IAP protected resource
);

Related Issues

Checklist

• I read the [Contributor Guide] and followed the process outlined there for submitting PRs.
• My PR includes unit or integration tests for all changed/updated/fixed behaviors (See [Contributor Guide]).
• All existing and new tests are passing.
• I updated/added relevant documentation (doc comments with ///).
• The analyzer (flutter analyze) does not report any problems on my PR.
• I read and followed the [Flutter Style Guide].
• The title of the PR starts with the name of the plugin surrounded by square brackets, e.g. [shared_preferences]
• I updated pubspec.yaml with an appropriate new version according to the [pub versioning philosophy].
• I updated CHANGELOG.md to add a description of the change.
• I signed the [CLA].
• I am willing to follow-up on review comments in a timely manner.

Breaking Change

• Yes, this is a breaking change (please indicate a breaking change in CHANGELOG.md and increment major revision).
• No, this is not a breaking change.