TransformedBounds is never set with composition renderer

[amwx]

Describe the bug

Also affects HitTestCustom if visual doesn't implement ICustomSimpleHitTest since the fallback is to test the point in the TransformedBounds

Avalonia/src/Avalonia.Base/Rendering/ICustomSimpleHitTest.cs

Lines 27 to 28 in af1c316

	public static bool HitTestCustom(this IVisual visual, Point point)
	=> (visual as ICustomSimpleHitTest)?.HitTest(point) ?? visual.TransformedBounds?.Contains(point) == true;

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• Version [e.g. 0.10.0-rc1 or 0.9.12]

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[maxkatz6]

I believe it's by design and TransformedBounds was planned to be removed and alternative solutions provided.
CC @kekekeks

[kekekeks]

We can add GetTransformedBounds method which would read the most-recent value. We can't have a property with change notification.

[amwx]

BTW this is fine - I was only using indirectly from .HitTestCustom() which I've removed now anyway.

Was this in the change log with the new renderer? If so, that's my bad. If not I'd add it. This threw me for a loop briefly after moving to 11.0 and This comment indicates other libraries use this property