Make GroupSelection into a Scene extension method

MatterControl.csproj

@@ -229,7 +229,6 @@
     <Compile Include="PartPreviewWindow\View3D\UndoCommands\TransformUndoCommand.cs" />
     <Compile Include="PartPreviewWindow\View3D\View3DAutoArange.cs" />
     <Compile Include="PartPreviewWindow\View3D\View3DCopyGroup.cs" />
-    <Compile Include="PartPreviewWindow\View3D\View3DGroup.cs" />
     <Compile Include="PartPreviewWindow\View3D\SceneActions.cs" />
     <Compile Include="PartPreviewWindow\View3D\SideBar\MirrorControls.cs" />
     <Compile Include="PartPreviewWindow\View3D\IObject3DEditor.cs" />

PartPreviewWindow/View3D/SceneActions.cs

@@ -215,5 +215,40 @@ namespace MatterHackers.MatterControl.PartPreviewWindow
 			}
 		}
 
+		public static async void GroupSelection(this InteractiveScene Scene, View3DWidget view3DWidget)
+		{
+			if (Scene.HasChildren)
+			{
+				view3DWidget.processingProgressControl.PercentComplete = 0;
+				view3DWidget.processingProgressControl.Visible = true;
+				view3DWidget.LockEditControls();
+				view3DWidget.viewIsInEditModePreLock = true;
+
+				var item = Scene.SelectedItem;
+
+				await Task.Run(() =>
+				{
+					if (Scene.IsSelected(Object3DTypes.SelectionGroup))
+					{
+						// Create and perform the delete operation
+						var operation = new GroupCommand(view3DWidget, Scene.SelectedItem);
+						operation.Do();
+
+						// Store the operation for undo/redo
+						view3DWidget.UndoBuffer.Add(operation);
+					}
+				});
+
+				if (view3DWidget.HasBeenClosed)
+				{
+					return;
+				}
+
+				view3DWidget.UnlockEditControls();
+
+				view3DWidget.Invalidate();
+			}
+		}
+
 	}
 }

PartPreviewWindow/View3D/View3DGroup.cs

@@ -1,72 +0,0 @@
-/*
-Copyright (c) 2014, Lars Brubaker
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are met:
-
-1. Redistributions of source code must retain the above copyright notice, this
-   list of conditions and the following disclaimer.
-2. Redistributions in binary form must reproduce the above copyright notice,
-   this list of conditions and the following disclaimer in the documentation
-   and/or other materials provided with the distribution.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
-ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
-ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
-(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
-LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
-ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-The views and conclusions contained in the software and documentation are those
-of the authors and should not be interpreted as representing official policies,
-either expressed or implied, of the FreeBSD Project.
-*/
-
-using MatterHackers.DataConverters3D;
-using System.Threading.Tasks;
-
-namespace MatterHackers.MatterControl.PartPreviewWindow
-{
-	public partial class View3DWidget
-	{
-		private async void GroupSelection()
-		{
-			if (Scene.HasChildren)
-			{
-				processingProgressControl.PercentComplete = 0;
-				processingProgressControl.Visible = true;
-				LockEditControls();
-				viewIsInEditModePreLock = true;
-
-				var item = Scene.SelectedItem;
-
-				await Task.Run(() =>
-				{
-					if (Scene.IsSelected(Object3DTypes.SelectionGroup))
-					{
-						// Create and perform the delete operation
-						var operation = new GroupCommand(this, Scene.SelectedItem);
-						operation.Do();
-
-						// Store the operation for undo/redo
-						UndoBuffer.Add(operation);
-					}
-				});
-
-				if (HasBeenClosed)
-				{
-					return;
-				}
-
-				UnlockEditControls();
-
-				Invalidate();
-			}
-		}
-	}
-}

PartPreviewWindow/View3D/View3DWidget.cs

@@ -363,7 +363,7 @@ namespace MatterHackers.MatterControl.PartPreviewWindow
 					doEdittingButtonsContainer.AddChild(groupButton);
 					groupButton.Click += (sender, e) =>
 					{
-						GroupSelection();
+						this.Scene.GroupSelection(this);
 					};
 
 					Button alignButton = smallMarginButtonFactory.Generate("Align".Localize());