Fix #2017: Make sure we never use an empty string as tab header

ILSpy/Properties/Resources.Designer.cs

@@ -1533,6 +1533,15 @@ namespace ICSharpCode.ILSpy.Properties {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to New Tab.
+        /// </summary>
+        public static string NewTab {
+            get {
+                return ResourceManager.GetString("NewTab", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Nuget Package Browser.
         /// </summary>

ILSpy/Properties/Resources.resx

@@ -876,4 +876,7 @@ Do you want to continue?</value>
 
 Do you want to proceed?</value>
   </data>
+  <data name="NewTab" xml:space="preserve">
+    <value>New Tab</value>
+  </data>
 </root>

ILSpy/TextView/AvalonEditTextOutput.cs

@@ -82,7 +82,7 @@ namespace ICSharpCode.ILSpy.TextView
 
 		public string IndentationString { get; set; } = "\t";
 
-		public string Title { get; set; }
+		public string Title { get; set; } = Properties.Resources.NewTab;
 
 		/// <summary>
 		/// Gets/sets the <see cref="Uri"/> that is displayed by this view.

ILSpy/ViewModels/TabPageModel.cs

@@ -28,6 +28,11 @@ namespace ICSharpCode.ILSpy.ViewModels
 	{
 		private readonly Dictionary<Language, LanguageVersion> languageVersionHistory = new Dictionary<Language, LanguageVersion>();
 
+		public TabPageModel()
+		{
+			this.Title = Properties.Resources.NewTab;
+		}
+
 		private Language language;
 		public Language Language {
 			get => language;