Create borders on demand

ReactWindows/ReactNative.Shared/ReactNative.Shared.projitems

@@ -146,12 +146,10 @@
     <Compile Include="$(MSBuildThisFileDirectory)UIManager\Annotations\ReactPropBaseAttribute.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)UIManager\Annotations\ReactPropGroupAttribute.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)UIManager\AppRegistry.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)UIManager\BorderedCanvasManager.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)UIManager\BorderedViewParentManager.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)UIManager\BorderedCanvas.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)UIManager\BorderExtensions.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)UIManager\ColorHelpers.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)UIManager\IUIBlock.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)UIManager\ReactShadowNodeExtensions.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)UIManager\ReactShadowNodeVisitor.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)UIManager\DependencyObjectExtensions.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)UIManager\DependencyObjectViewManager.cs" />

ReactWindows/ReactNative.Shared/UIManager/BorderedCanvas.cs

@@ -0,0 +1,44 @@
+using System;
+
+#if WINDOWS_UWP
+using Windows.UI.Xaml;
+using Windows.UI.Xaml.Controls;
+using Windows.UI.Xaml.Data;
+#else
+using System.Windows;
+using System.Windows.Controls;
+#endif
+
+namespace ReactNative.UIManager
+{
+    /// <summary>
+    /// Represents a Canvas with an optional Border inside.
+    /// </summary>
+    public class BorderedCanvas : Canvas
+    {
+        private Border _border = null;
+
+        /// <summary>
+        /// The Border associated with this Canvas or null if it doesn't have a border.
+        /// The Border is always the first element in the Children collection.
+        /// </summary>
+        public Border Border
+        {
+            get
+            {
+                return _border;
+            }
+            set
+            {
+                if (_border != null)
+                {
+                    throw new InvalidOperationException("The Canvas already has a Border");
+                }
+
+                _border = value;
+
+                Children.Insert(0, _border);
+            }
+        }
+    }
+}