Handle Settings.UsingDeclarations and Settings.FullyQualifyAmbiguousTypeNames correctly.

ICSharpCode.Decompiler/CSharp/Transforms/IntroduceUsingDeclarations.cs

@@ -32,8 +32,6 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 	/// </summary>
 	public class IntroduceUsingDeclarations : IAstTransform
 	{
-		public bool FullyQualifyAmbiguousTypeNames = true;
-		
 		public void Run(AstNode rootNode, TransformContext context)
 		{
 			// First determine all the namespaces that need to be imported:
@@ -42,6 +40,7 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 			
 			var usingScope = new UsingScope();
 
+			if (context.Settings.UsingDeclarations) {
 				var insertionPoint = rootNode.Children.LastOrDefault(n => n is PreProcessorDirective p && p.Type == PreProcessorDirectiveType.Define);
 
 				// Now add using declarations for those namespaces:
@@ -53,15 +52,16 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 					for (int i = 1; i < parts.Length; i++) {
 						nsType = new MemberType { Target = nsType, MemberName = parts[i] };
 					}
-				if (FullyQualifyAmbiguousTypeNames) {
+					if (context.Settings.FullyQualifyAmbiguousTypeNames) {
 						var reference = nsType.ToTypeReference(NameLookupMode.TypeInUsingDeclaration) as TypeOrNamespaceReference;
 						if (reference != null)
 							usingScope.Usings.Add(reference);
 					}
 					rootNode.InsertChildAfter(insertionPoint, new UsingDeclaration { Import = nsType }, SyntaxTree.MemberRole);
 				}
+			}
 
-			if (!FullyQualifyAmbiguousTypeNames)
+			if (!context.Settings.FullyQualifyAmbiguousTypeNames)
 				return;
 
 			// verify that the SimpleTypes refer to the correct type (no ambiguities)