refactor: Add partials to classes for Uno Platform

This change enables Uno Platform compatibility forward compatibility.

Author: jeromelaban

Microsoft.Toolkit.Uwp.DeveloperTools/AlignmentGrid/AlignmentGrid.cs

@@ -12,7 +12,7 @@ namespace Microsoft.Toolkit.Uwp.DeveloperTools
     /// <summary>
     /// AlignmentGrid is used to display a grid to help aligning controls
     /// </summary>
-    public class AlignmentGrid : ContentControl
+    public partial class AlignmentGrid : ContentControl
     {
         /// <summary>
         /// Identifies the <see cref="LineBrush"/> dependency property.

Microsoft.Toolkit.Uwp.DeveloperTools/FocusTracker/FocusTracker.cs

@@ -24,7 +24,7 @@ namespace Microsoft.Toolkit.Uwp.DeveloperTools
     [TemplatePart(Name = "ControlType", Type = typeof(TextBlock))]
     [TemplatePart(Name = "ControlAutomationName", Type = typeof(TextBlock))]
     [TemplatePart(Name = "ControlFirstParentWithName", Type = typeof(TextBlock))]
-    public class FocusTracker : Control
+    public partial class FocusTracker : Control
     {
         /// <summary>
         /// Defines the <see cref="IsActive"/> dependency property.

Microsoft.Toolkit.Uwp.UI.Animations/CompositionAnimations/Animations/AnimationBase.cs

@@ -14,7 +14,7 @@ namespace Microsoft.Toolkit.Uwp.UI.Animations
     /// Abstract class providing common dependency properties for composition animations
     /// </summary>
     [ContentProperty(Name = nameof(KeyFrames))]
-    public abstract class AnimationBase : DependencyObject
+    public abstract partial class AnimationBase : DependencyObject
     {
         /// <summary>
         /// Identifies the <see cref="Target"/> property

Microsoft.Toolkit.Uwp.UI.Animations/CompositionAnimations/KeyFrames/KeyFrame.cs

@@ -9,7 +9,7 @@ namespace Microsoft.Toolkit.Uwp.UI.Animations
     /// <summary>
     /// Provides common Dependency properties for KeyFrames
     /// </summary>
-    public abstract class KeyFrame : DependencyObject
+    public abstract partial class KeyFrame : DependencyObject
     {
         /// <summary>
         /// Identifies the <see cref="Key"/> dependency property

Microsoft.Toolkit.Uwp.UI.Animations/Extensions/AnimationTools.cs

@@ -9,7 +9,7 @@ namespace Microsoft.Toolkit.Uwp.UI.Animations
     /// <summary>
     /// Internal tool to link composite transforms to elements
     /// </summary>
-    internal class AnimationTools : DependencyObject
+    internal partial class AnimationTools : DependencyObject
     {
         /// <summary>
         /// Attached property used to link composite transform with UIElement

Microsoft.Toolkit.Uwp.UI.Controls/Carousel/Carousel.cs

@@ -20,7 +20,7 @@ namespace Microsoft.Toolkit.Uwp.UI.Controls
     /// <summary>
     /// A modern UI Carousel control. Really flexible. Works with touch, keyboard, mouse.
     /// </summary>
-    public class Carousel : ItemsControl
+    public partial class Carousel : ItemsControl
     {
         /// <summary>
         /// Gets or sets the selected item.

Microsoft.Toolkit.Uwp.UI.Controls/Carousel/CarouselItem.cs

@@ -13,7 +13,7 @@ namespace Microsoft.Toolkit.Uwp.UI.Controls
     /// <summary>
     /// Represents the container for an item in a Carousel control.
     /// </summary>
-    public class CarouselItem : SelectorItem
+    public partial class CarouselItem : SelectorItem
     {
         private const string PointerOverState = "PointerOver";
         private const string PointerOverSelectedState = "PointerOverSelected";

Microsoft.Toolkit.Uwp.UI.Controls/Carousel/CarouselPanel.cs

@@ -18,7 +18,7 @@ namespace Microsoft.Toolkit.Uwp.UI.Controls
     /// <summary>
     /// The panel used in the <see cref="Carousel"/> control
     /// </summary>
-    public class CarouselPanel : Panel
+    public partial class CarouselPanel : Panel
     {
         // Storyboard on gesture
         private Storyboard storyboard = new Storyboard();

Microsoft.Toolkit.Uwp.UI.Controls/ColorPicker/ColorPickerButton.cs

@@ -17,7 +17,7 @@ namespace Microsoft.Toolkit.Uwp.UI.Controls
     /// A <see cref="DropDownButton"/> which displays a color as its <c>Content</c> and it's <c>Flyout</c> is a <see cref="ColorPicker"/>.
     /// </summary>
     [TemplatePart(Name = nameof(CheckeredBackgroundBorder), Type = typeof(Border))]
-    public class ColorPickerButton : DropDownButton
+    public partial class ColorPickerButton : DropDownButton
     {
         /// <summary>
         /// Gets the <see cref="Controls.ColorPicker"/> instances contained by the <see cref="DropDownButton"/>.

Microsoft.Toolkit.Uwp.UI.Controls/HeaderedContentControl/HeaderedContentControl.cs

@@ -10,7 +10,7 @@ namespace Microsoft.Toolkit.Uwp.UI.Controls
     /// <summary>
     /// Provides the base implementation for all controls that contain single content and have a header.
     /// </summary>
-    public class HeaderedContentControl : ContentControl
+    public partial class HeaderedContentControl : ContentControl
     {
         private const string PartHeaderPresenter = "HeaderPresenter";