* Enable nullability in UnitTests
* Enable nullability in Base.UnitTests
* Enable nullability in Markup.UnitTests
* Enable nullability in Markup.Xaml.UnitTests
* Merge core libraries.
Everything below `Avalonia.Controls` into `Avalonia.Base`.
* Move new files to correct place.
* Removed unused dirs/projects,
* Removed outdated references from theme assemblies.
* Merge unit tests to match new assembly layout.
* Fixup test namespaces.
* Make directory match namespace.
* Move files to match namespace.
* Move files to match namespace.
* Fix up incorrect namespace.
`Avalonia.Visuals.Media.Imaging` -> `Avalonia.Media.Imaging`.
* Fix resource URL.
* Removed outdated dependencies.
* Added missing project reference.
* Update test namespaces.
* Fix merge error.
* Fix merge errors.
* Fix bad merge in WindowsInteropTest.csproj.
* Fix up merge errors in csprojs.
* Remove merged tests from nuke.
* Fix up namespace.
* Fix compile error.
* Fix failing tests.
Now that more unit tests are present in Avalonia.Base.UnitTests, general `AvaloniaObject` properties are getting registered. Ignore those.
Co-authored-by: Jumar Macato <16554748+jmacato@users.noreply.github.com>
- Don't use Rx in the styling system. Instead introduces `IStyleActivator` which is like an `IObservable<bool>`-lite in order to cut down on allocations.
- #nullable enable on touched files
A lot of time was being spent calling `Attach` on styles that will never match a control. On the first pass, cache the styles that can match a particular control type and use this cache to bypass styles that will never match on subsequent passes.