Revert "Fixes AlternatingRowForeground not being applied"

This reverts commit 53bc957.

Author: thiago-cs

Microsoft.Toolkit.Uwp.UI.Controls.DataGrid/DataGrid/DataGridRow.cs

@@ -1122,11 +1122,40 @@ internal void EnsureForeground()
             {
                 DiagnosticsDebug.Assert(this.Index != -1, "Expected Index other than -1.");
 
-                var newForeground = this.Index % 2 == 0 || this.OwningGrid.AlternatingRowForeground == null
-                    ? this.OwningGrid.RowForeground
-                    : this.OwningGrid.AlternatingRowForeground;
+                PropertyMetadata metadataInfo = DataGridRow.ForegroundProperty.GetMetadata(typeof(DataGridRow));
+                Brush defaultForeground = metadataInfo == null ? null : metadataInfo.DefaultValue as Brush;
+                Brush newForeground = null;
 
-                this.ComputedForeground = newForeground ?? this.Foreground;
+                if (this.Foreground.Equals(defaultForeground))
+                {
+                    if (this.Index % 2 == 0 || this.OwningGrid.AlternatingRowForeground == null)
+                    {
+                        // Use OwningGrid.RowForeground if the index is even or if the OwningGrid.AlternatingRowForeground is null
+                        if (this.OwningGrid.RowForeground != null)
+                        {
+                            newForeground = this.OwningGrid.RowForeground;
+                        }
+                    }
+                    else
+                    {
+                        // Alternate row
+                        if (this.OwningGrid.AlternatingRowForeground != null)
+                        {
+                            newForeground = this.OwningGrid.AlternatingRowForeground;
+                        }
+                    }
+
+                    if (newForeground == null)
+                    {
+                        newForeground = this.Foreground;
+                    }
+                }
+                else
+                {
+                    newForeground = this.Foreground;
+                }
+
+                this.ComputedForeground = newForeground;
             }
             else
             {
@@ -1502,4 +1531,4 @@ public int Debug_Index
         }
 #endif
     }
-}
+}