Resize meshContentProvider result if required, fix SetUnsized bug

- Issue MatterHackers/MCCentral#4347
Fix thumbnail centering for missing item

MatterControlLib/ControlElements/MHDropDownList.cs

@@ -88,11 +88,6 @@ namespace MatterHackers.MatterControl
 		{
 			get
 			{
-				if (menuVisible)
-				{
-					var a = 1;
-				}
-
 				if (base.BackgroundColor != Color.Transparent)
 				{
 					return base.BackgroundColor;
@@ -112,10 +107,6 @@ namespace MatterHackers.MatterControl
 			}
 			set
 			{
-				if (value.GetAsHTMLString() == "#333333")
-				{
-					var a = 1;
-				}
 				base.BackgroundColor = value;
 			}
 

MatterControlLib/Library/ContentProviders/MeshContentProvider.cs

@@ -101,7 +101,6 @@ namespace MatterHackers.MatterControl
 			});
 		}
 
-
 		public async Task<ImageBuffer> GetThumbnail(ILibraryItem libraryItem, int width, int height)
 		{
 			IObject3D object3D = null;
@@ -175,6 +174,6 @@ namespace MatterHackers.MatterControl
 				allowMultiThreading: !ApplicationController.Instance.ActivePrinter.Connection.PrinterIsPrinting);
 		}
 
-		public ImageBuffer DefaultImage => AggContext.StaticData.LoadIcon("mesh.png");
+		public ImageBuffer DefaultImage { get; } = AggContext.StaticData.LoadIcon("mesh.png");
 	}
 }

MatterControlLib/Library/Widgets/ListView/ListViewItemBase.cs

@@ -121,7 +121,15 @@ namespace MatterHackers.MatterControl.CustomWidgets
 						requeueRaytraceOnDraw = false;
 						raytracePending = false;
 
-						this.SetSizedThumbnail(thumbnail);
+						if (thumbnail.Width != thumbWidth
+						|| thumbnail.Height != thumbHeight)
+						{
+							this.SetUnsizedThumbnail(thumbnail);
+						}
+						else
+						{
+							this.SetSizedThumbnail(thumbnail);
+						}
 					}
 				}
 			});
@@ -184,7 +192,7 @@ namespace MatterHackers.MatterControl.CustomWidgets
 		{
 			this.SetSizedThumbnail(
 				ApplicationController.Instance.Library.EnsureCorrectThumbnailSizing(
-					theme.GeneratingThumbnailIcon,
+					thumbnail,
 					thumbWidth,
 					thumbHeight));
 		}