Add LayerGCodeHasExpectedValue test

- Immutable PrinterSettings.BaseLayer
- Add PrinterSettings.AutoSave flag to support disabling autosave
  - Save to default path fails under test
- Add PrinterSettings.Save(path) to support manual save
- Migrate 'active_quality_key' to SettingsKey class

SlicerConfiguration/Settings/PrinterSettings.cs

@@ -57,8 +57,6 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 
 		public static RootedObjectEventHandler PrintLevelingEnabledChanged = new RootedObjectEventHandler();
 
-		private static PrinterSettingsLayer baseLayerCache;
-
 		public static PrinterSettings Empty { get; }
 
 		public int DocumentVersion { get; set; } = LatestVersion;
@@ -110,7 +108,7 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 				}
 			}
 		}
-		
+
 		[OnDeserialized]
 		internal void OnDeserializedMethod(StreamingContext context)
 		{
@@ -132,7 +130,7 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 				"layer_id",
 			};
 
-			if(!setLayerName)
+			if (!setLayerName)
 			{
 				skipKeys.Add(SettingsKey.layer_name);
 			}
@@ -146,9 +144,6 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 
 			var sourceFilter = rawSourceFilter.Where(layer => layer != null);
 
-			var baseLayer = settingsToImport.BaseLayer;
-			settingsToImport.BaseLayer = new PrinterSettingsLayer();
-
 			foreach (var keyName in PrinterSettings.KnownSettings)
 			{
 				if (settingsToImport.Contains(keyName))
@@ -171,8 +166,6 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 				destinationLayer[SettingsKey.layer_name] = settingsToImport.GetValue(SettingsKey.layer_name, sourceFilter);
 			}
 
-			settingsToImport.BaseLayer = baseLayer;
-
 			this.Save();
 
 			ApplicationController.Instance.ReloadAdvancedControlsPanel();
@@ -197,11 +190,11 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 		{
 			get
 			{
-				return GetValue("active_quality_key");
+				return GetValue(SettingsKey.active_quality_key);
 			}
 			internal set
 			{
-				SetValue("active_quality_key", value);
+				SetValue(SettingsKey.active_quality_key, value);
 				QualityLayer = GetQualityLayer(value);
 				Save();
 			}
@@ -267,17 +260,25 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 				return SHA1;
 			}
 		}
-		
+
 		private string DocumentPath => ProfileManager.Instance.ProfilePath(this.ID);
 
+		[JsonIgnore]
+		public bool AutoSave { get; set; } = true;
+
 		public void Save()
 		{
 			// Skip save operation if on the EmptyProfile
-			if (!this.PrinterSelected)
+			if (!this.PrinterSelected || !this.AutoSave)
 			{
 				return;
 			}
 
+			Save(DocumentPath);
+		}
+
+		public void Save(string filePath)
+		{
 			lock (writeLock)
 			{
 				string json = this.ToJson();
@@ -289,7 +290,7 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 					ProfileManager.Instance.Save();
 				}
 
-				File.WriteAllText(DocumentPath, json);
+				File.WriteAllText(filePath, json);
 			}
 
 			if (ActiveSliceSettings.Instance?.ID == this.ID)
@@ -510,23 +511,7 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 		}
 
 		[JsonIgnore]
-		public PrinterSettingsLayer BaseLayer
-		{
-			get
-			{
-				if (baseLayerCache == null)
-				{
-					baseLayerCache = SliceSettingsOrganizer.Instance.GetDefaultSettings();
-				}
-
-				return baseLayerCache;
-			}
-
-			internal set
-			{
-				baseLayerCache = value;
-			}
-		}
+		public PrinterSettingsLayer BaseLayer { get; set; } = SliceSettingsOrganizer.Instance.GetDefaultSettings();
 
 		private IEnumerable<PrinterSettingsLayer> defaultLayerCascade
 		{

SlicerConfiguration/Settings/ProfileMigrations.cs

@@ -234,7 +234,7 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 								break;
 
 							case "MatterControl.ActiveQualityKey":
-								layer.Add("active_quality_key", item.Value);
+								layer.Add(SettingsKey.active_quality_key, item.Value);
 								break;
 
 							case "MatterControl.ActiveMaterialKey":

SlicerConfiguration/Settings/SettingsHelpers.cs

@@ -112,6 +112,7 @@ namespace MatterHackers.MatterControl.SlicerConfiguration
 		public const string ip_address = nameof(ip_address);
 		public const string ip_port = nameof(ip_port);
 		public const string first_layer_speed = nameof(first_layer_speed);
+		public const string active_quality_key = nameof(active_quality_key);
 	}
 
 	public class SettingsHelpers