[Breaking Change] Layer.replaceWith is being removed

[Yegor Jbanov]

In https://github.com/flutter/flutter/pull/33164 I propose that we remove the Layer.replaceWith method. This method is not used by the Flutter framework, and we lack tests for it. Therefore its behavior is undefined.

This fixes https://github.com/flutter/flutter/issues/33015

To update your code simply stop using this method. Instead of replacing a layer, recreate the child list by first calling ContainerLayer.removeAllChildren then calling ContainerLayer.append for each child in the order they should appear in the child list.

Please, don't hesitate to reply here if this method is important for you. We could reevaluate removing it, and add sufficient test coverage for it instead.

[Yegor Jbanov]

Update: the PR was submitted https://github.com/flutter/flutter/commit/8217f4bc8c80ad639e7759cca0007f20c49a28a8