Apply patch for #U4-1156 - IFileSystem public changes.

src/Umbraco.Core/IO/FileSystemWrapper.cs

@@ -15,8 +15,7 @@ namespace Umbraco.Core.IO
 	/// 
 	/// This abstract class just wraps the 'real' IFileSystem object passed in to its constructor.
 	/// </remarks>
-	[UmbracoExperimentalFeature("http://issues.umbraco.org/issue/U4-1156", "Will be declared public after 4.10")]
-	internal abstract class FileSystemWrapper : IFileSystem
+	public abstract class FileSystemWrapper : IFileSystem
 	{
 		private readonly IFileSystem _wrapped;
 

src/Umbraco.Core/IO/IFileSystem.cs

@@ -4,9 +4,8 @@ using System.IO;
 using Umbraco.Core.CodeAnnotations;
 
 namespace Umbraco.Core.IO
-{
-	[UmbracoExperimentalFeature("http://issues.umbraco.org/issue/U4-1156", "Will be declared public after 4.10")]
-    internal interface IFileSystem
+{	
+    public interface IFileSystem
     {
         IEnumerable<string> GetDirectories(string path);
 

src/Umbraco.Core/IO/MediaFileSystem.cs

@@ -11,8 +11,7 @@ namespace Umbraco.Core.IO
 	/// A custom file system provider for media
 	/// </summary>
 	[FileSystemProvider("media")]
-	[UmbracoExperimentalFeature("http://issues.umbraco.org/issue/U4-1156", "Will be declared public after 4.10")]
-	internal class MediaFileSystem : FileSystemWrapper
+	public class MediaFileSystem : FileSystemWrapper
 	{
 		public MediaFileSystem(IFileSystem wrapped)
 			: base(wrapped)

src/Umbraco.Core/IO/PhysicalFileSystem.cs

@@ -9,8 +9,7 @@ using Umbraco.Core.Logging;
 
 namespace Umbraco.Core.IO
 {
-	[UmbracoExperimentalFeature("http://issues.umbraco.org/issue/U4-1156", "Will be declared public after 4.10")]
-    internal class PhysicalFileSystem : IFileSystem
+    public class PhysicalFileSystem : IFileSystem
     {
         private readonly string _rootPath;
         private readonly string _rootUrl;