Redrawn CollectionView with Handler2 binds items that shouldn't be bound

[rabuckley]

Description

CollectionView with CollectionViewHandler2 draws items that shouldn't be (or at least aren't with the default handler) drawn when resizing on iOS.

See the debug output and the performance difference. With default CollectionViewHandler:

collection-view-1.mp4

With CollectionViewHandler2:

collection-view-2.mp4

(The border rendering issues in Handler2 are #27608)

Steps to Reproduce

1. Clone repository https://github.com/rabuckley/maui-cvh2-render-perf
2. Run the app on iOS and change the span of the grid layout.
3. Observe diagnostics in debug output and noticeable lag.

Comment ConfigureMauiHandlers in MauiProgram.cs to view the old/expected performance/behaviour.

Link to public reproduction project repository

https://github.com/rabuckley/maui-cvh2-render-perf

Version with bug

9.0.30 SR3

Is this a regression from previous behavior?

No.

Affected platforms

iOS

[Marnie-Majait]

This issue has been verified using Visual Studio 17.14 Preview 1(9.0.40 & 9.0.30 & 9.0.22 & 9.0.0). Can repro this issue on iOS platform.