Rename serialization methods in DevTools to meet recommended standard.

[polina-c]

https://docs.flutter.dev/data-and-backend/serialization/json#serializing-json-inside-model-classes

[kenzieschmoll]

Can we revert all the renames in devtools_app_shared, devtools_extensions, and devtools_shared? These are breaking changes that will cause unnecessary churn for users of these packages.

[kenzieschmoll]

Or another option for these packages is to mark the existing methods deprecated with a message to use the new methods. But this may be overkill for a rename.

[polina-c]

Can we revert all the renames in devtools_app_shared, devtools_extensions, and devtools_shared? These are breaking changes that will cause unnecessary churn for users of these packages.

Reverted

[auto-submit]

auto label is removed for flutter/devtools/7584, due to - The status or check suite devtools_app integration-test integration_dart2js - flutter - shard 3/3 has failed. Please fix the issues identified (or deflake) before re-applying this label.

[auto-submit]

auto label is removed for flutter/devtools/7584, due to - The status or check suite devtools_app integration-test integration_dart2js - flutter - shard 3/3 has failed. Please fix the issues identified (or deflake) before re-applying this label.