Split resource nodes into two types:
- `IResourceHost` represents controls and `Application`
- `IResourceProvider` represents resource dictionaries and styles, these are owned by `IResourceHost`s
Dynamic resources are now always resolved from an `IResourceHost`: if an `IResourceProvider` doesn't have a host then a dynamic resource in the resource provider will not be resolved. Resource providers no longer have a `ResourcesChanged` event, instead they notify their `IResourceHost` owner of a resource change by calling the `NotifyHostedResourcesChanged` method.
This requires that a `<Transitions>` element is used to contain the transitions in XAML and a `new Transitions()` is used when assigning transitions from code.
- Pass information for all property changes to `OnPropertyChangedCore`; whether they result in an effective value change or not
- Added `GetBaseValue` to get a value with a specified priority
- Change the signature of `OnPropertyChanged` again to take an `AvaloniaPropertyChangedEventArgs<T>`
And implement the functionality in the content controls themselves. `ContentControlMixin` was too complex and even with its complexity had bugs (such as in #2821). By moving the functionality to the content controls there is some repeated code but it's much more straightforward.
...to `Avalonia.Markup.Xaml`. Also added tests: tests required a new instance of `AvaloniaXamlSchemaContext` for each `AvaloniaXamlLoader` as otherwise one test can affect other tests.
This is a relic from when we were targeting a PCL profile that didn't have `System.ComponentModel.ISupportInitialize`. Now that we have that, use it instead.
The changes made to the animation system in #1768 currently needs to be able to set any property on any object in order for animations on transforms to work.
Steven Kirk
Andrey Kunchev
Nikita Tsukanov
Steven Kirk