Most (but not all) tests passing, all features mostly implemented exception coercion.

To remove `InheritanceFrame` - it was unneeded, we can just point to the nearest ancestor value store with inherited values.

With associated unit tests.

- Always evaluate the active state from current information, don't rely on subscriptions to fire as the current state may not be up-to-date
- Don't notify the `IStyleActivatorSink` of a change immediately on subscription

And use the concrete `ValueFrame` (renamed from `ValueFrameBase`) as this was the only implementation of the interface.

If a `StyleBase` has no activator, and its `Setter`s don't need to be separately instanced on the control, then we can share a `StyleInstance` between controls.

This causes failing tests because `TopLevel` applies styles in its constructor, but doesn't set `_styled` to true, meaning that styles get applied twice. This issue will need to be addressed separately.

Due to #8549.

And rename collection to indicate this.

And fixed a couple of bugs.

…-store

And remove the duplicate setter that we have.

…-store

This can happen when re-evaluating the value store if a style is detached before its frame is evaluated.

We already have a place to store them in the `_localValueBindings` list, so use that rather than having a separate `_directBindings` list in `AvaloniaObject`.

Seems it's slightly faster to re-evaluate the single value in this case.

Should fix leak tests.

We should be unsubscribing from bindings when a higher priority binding or value is added.

Too many gotchas in implementing binding entries, we'll take the performance hit of a few virtual method calls.

Make two-way bindings in setters not write to source when inactive.

The value store alone cannot fix these tests, as writing back to source in two-way bindings is implemented at a higher level than the value store. We'll need to refactor the way two-way bindings work in a separate PR.

When re-evaluating a single property, if the frame activation state changes then we need to re-evaluate all properties.

Previously, the `IsActive` property caused the activator state to be re-evaluated, which meant that when the _debugger_ read it, it was re-evaluated, making debugging difficult.

They're no longer needed.

When re-evaluating a single property, if the frame activation state  changes when unsubscribing from inactive frames then we need to re-evaluate all properties.

Even if the frame's activation state has changed to false.

When raising `PropertyChanged` due to setting the inheritance parent, use the closest value in the inheritance tree rather than the furthest.

It's unsuitable for our needs as there's no way to make an observable fire on subscribe.

Ensure `rootGetter` is evaluated each time the observer is initialized; plus failing and now passing test.

Avoids a virtual call in the case of styled properties.

Calling `DisposeAndRaiseUnset` can cause a nested reevaluation of property values.