Revert Applying visibility change to child controls

[jfversluis]

Description of Change

Reverts #20154 since it caused unexpected behavior for a lot of folks.

Reverting now and then improve on this and try again at a later stage.

Fixes #28677
Fixes #28415

cc: @kubaflo

[Copilot]

Pull Request Overview

This PR reverts a previous change that affected the propagation of visibility to child controls. The key changes include:

• Reverting assertions and behavior related to visibility propagation in both test and production code.
• Removing tests that validate the propagation of the IsVisible property.
• Simplifying the VisualElement implementation by eliminating custom propagation logic.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/Controls/tests/Xaml.UnitTests/Issues/Issue1549.cs	Added an assertion on InvertBoolenConverter.count to reflect the reverted behavior
src/Controls/tests/Core.UnitTests/VisualElementTests.cs	Removed tests validating visibility propagation to child controls
src/Controls/src/Core/VisualElement/VisualElement.cs	Removed property propagation calls and helper methods related to IsVisible

Comments suppressed due to low confidence (3)

src/Controls/tests/Xaml.UnitTests/Issues/Issue1549.cs:192

• Please confirm that the assertion expecting InvertBoolenConverter.count to be 4 is stable given the revert; if this value is based on prior behavior, a brief code comment explaining the expected count would help avoid future confusion.

Assert.AreEqual(4, InvertBoolenConverter.count);

src/Controls/tests/Core.UnitTests/VisualElementTests.cs:317

• The tests for propagating visibility to child controls have been removed as part of the revert; please ensure that equivalent coverage is maintained in TestCases.HostApp and TestCases.Shared.Tests if this behavior is revisited in future releases.

[Fact] public void ShouldPropagateVisibilityToChildren() { ... }

src/Controls/src/Core/VisualElement/VisualElement.cs:1501

• The removal of the IsVisible property propagation call in OnIsVisibleChanged aligns with the revert; please double-check that this change does not disrupt any internal state updates expected by the existing test suite.

(this as IPropertyPropagationController)?.PropagatePropertyChanged(IsVisibleProperty.PropertyName);

[PureWeen]

/rebase

[PureWeen]

/backport to release/9.0.1xx-sr5

[github-actions]

Started backporting to release/9.0.1xx-sr5: https://github.com/dotnet/maui/actions/runs/14342767821

[PureWeen]

• failing tests are unrelated

[bhavanesh2001]

@jfversluis Since the original PR was reverted, should the bugs it was meant to fix be reopened?