Fixed build.

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/trunk@2934 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/AddIns/DisplayBindings/ClassDiagram/ClassCanvas/Src/ClassCanvasItem.cs

@@ -259,17 +259,7 @@ namespace ClassDiagram
 		
 		protected IAmbience GetAmbience()
 		{
-			IAmbience ambience = null;
+			IAmbience ambience = AmbienceService.CurrentAmbience;
-			
-			try
-			{
-				ambience = AmbienceService.CurrentAmbience;
-			}
-			catch (NullReferenceException)
-			{
-				ambience = ICSharpCode.SharpDevelop.Dom.CSharp.CSharpAmbience.Instance;
-			}
-			
 			ambience.ConversionFlags = ConversionFlags.None;
 			return ambience;
 		}

src/AddIns/DisplayBindings/ClassDiagram/ClassEditor/ClassEditor.cs

@@ -489,19 +489,8 @@ namespace ClassDiagram
 		
 		protected IAmbience GetAmbience()
 		{
-			IAmbience ambience = null;
+			IAmbience ambience = AmbienceService.CurrentAmbience;
-			
-			try
-			{
-				ambience = AmbienceService.CurrentAmbience;
-			}
-			catch (NullReferenceException)
-			{
-				ambience = ICSharpCode.SharpDevelop.Dom.CSharp.CSharpAmbience.Instance;
-			}
-			
 			ambience.ConversionFlags = ConversionFlags.None;
-			
 			return ambience;
 		}
 		

src/Main/Base/Project/Src/Services/AmbienceService/AmbienceService.cs

@@ -79,18 +79,28 @@ namespace ICSharpCode.SharpDevelop
 		
 		public static IAmbience CurrentAmbience {
 			get {
+				Gui.WorkbenchSingleton.AssertMainThread();
+				
+				IAmbience ambience;
 				if (UseProjectAmbienceIfPossible) {
 					ICSharpCode.SharpDevelop.Project.IProject p = ICSharpCode.SharpDevelop.Project.ProjectService.CurrentProject;
 					if (p != null) {
-						return p.GetAmbience();
+						ambience = p.GetAmbience();
+						if (ambience != null)
+							return ambience;
 					}
 				}
 				if (defaultAmbience == null) {
 					string language = DefaultAmbienceName;
-					defaultAmbience = (IAmbience)AddInTree.BuildItem("/SharpDevelop/Workbench/Ambiences/" + language, null);
+					try {
-					if (defaultAmbience == null) {
+						ambience = (IAmbience)AddInTree.BuildItem("/SharpDevelop/Workbench/Ambiences/" + language, null);
+					} catch (TreePathNotFoundException) {
+						ambience = null;
+					}
+					if (ambience == null && Gui.WorkbenchSingleton.MainForm != null) {
 						MessageService.ShowError("${res:ICSharpCode.SharpDevelop.Services.AmbienceService.AmbienceNotFoundError}");
 					}
+					defaultAmbience = ambience ?? new NetAmbience();
 				}
 				return defaultAmbience;
 			}
@@ -108,7 +118,6 @@ namespace ICSharpCode.SharpDevelop
 		static void PropertyChanged(object sender, PropertyChangedEventArgs e)
 		{
 			if (e.Key == ambienceProperty) {
-				defaultAmbience = null;
 				OnAmbienceChanged(EventArgs.Empty);
 			}
 			if (e.Key == codeGenerationProperty) {