…ecesaary

Description

When ios swipe up to focus a collapsed sliver app bar, the semantics tree suddenly change its shape and ios accessibility api can not handle it. The root cause is in the native ios side. This pr is a workaround to prevent this situation by not changing the shape of semantics tree when it is not necessary.

Related Issues

Fixes #60331

Tests

I added the following tests:

existing test coverage

Checklist

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Breaking Change

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