Restore "Delete" tab functionality

The file was being deleted but the tab was still there

app/src/processing/app/Editor.java

@@ -1706,6 +1706,11 @@ public class Editor extends JFrame implements RunnerListener {
     tabs.add(tab);
   }
 
+  protected void removeTab(SketchFile file) throws IOException {
+    int index = findTabIndex(file);
+    tabs.remove(index);
+  }
+
   // . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 
   void handleFindReference(ActionEvent e) {

app/src/processing/app/SketchController.java

@@ -260,6 +260,8 @@ public class SketchController {
           return;
         }
 
+        editor.removeTab(current);
+
         // just set current tab to the main tab
         editor.selectTab(0);