[google_maps_flutter] Use super parameters in more places in examples

[srawlins]

Changes to the Dart analyzer will catch more situations where super-parameters should be used, for the use_super_parameters lint rule. We need to clean up this example code before it can land.

Work towards dart-lang/sdk#58729

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[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests or get an explicit test exemption before merging.

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[gemini-code-assist]

Code Review

This pull request updates numerous example files across the Google Maps Flutter packages to utilize the super.key constructor parameter shorthand. A review comment suggests moving the super.key parameter to the beginning of the parameter list in advanced_marker_icons.dart to maintain consistency with Flutter conventions and other constructors in the repository.

[srawlins]

@stuartmorgan-g would this change require a bump? It only affects example code, and is a runtime no-op.

[stuartmorgan-g]

The tool is correctly identifying that it doesn't require a version bump (since it doesn't change example/lib/main.dart), it's just flagging it to evaluate whether it warrants a CHANGELOG entry. This doesn't, since it's not showing anything relevant to package clients—the tool errs on the side of false positives, since some unpublished example changes are still relevant (e.g., if a new version of Android requires a plugin to put an new permission in it manifest, we would mention that in the CHANGELOG).

[stuartmorgan-g]

LGTM