Reland "Make Flutter version information accessible at runtime (#140783)"

[ueman]

Reverts #163753
Relands #140783

Original PR description below

---

This makes various Flutter version information available at runtime. It's basically the same as executing flutter --version. This is especially useful for tools like Crashlytics or Sentry (see for example getsentry/sentry-dart#416).

Usage example:

FlutterVersion.version;           // 3.16.5
FlutterVersion.channel;           // stable
FlutterVersion.gitUrl;            // https://github.com/flutter/flutter.git
FlutterVersion.frameworkRevision; // 78666c8dc5
FlutterVersion.engineRevision;    // 3f3e560236
FlutterVersion.dartVersion;       // 3.2.3

This approach has prior art as seen in #134179.

Fixes #61814

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel on Discord.

[bkonyi]

Thanks for re-uploading!

[auto-submit]

autosubmit label was removed for flutter/flutter/163761, because This PR has not met approval requirements for merging. The PR author is not a member of flutter-hackers and needs 1 more review(s) in order to merge this PR.

• Merge guidelines: A PR needs at least one approved review if the author is already part of flutter-hackers or two member reviews if the author is not a flutter-hacker before re-applying the autosubmit label. Reviewers: If you left a comment approving, please use the "approve" review action instead.

[ueman]

@bkonyi or @matanlurey I guess the auto submit label needs to be added again