Fixed dirty indicator of uncloseable widgets.

Closes #1034.

Signed-off-by: Akos Kitta <a.kitta@arduino.cc>

Author: Akos Kitta

Diff for: arduino-ide-extension/src/browser/style/editor.css

@@ -1,8 +1,7 @@
 /* Show the dirty indicator on unclosable widgets. On hover, it should still show the dot instead of the X. */
 /* https://github.com/arduino/arduino-pro-ide/issues/380 */
-.p-TabBar.theia-app-centers .p-TabBar-tab.p-mod-closable.theia-mod-dirty > .p-TabBar-tabCloseIcon:hover {
-    background-size: 13px;
-    background-image: var(--theia-icon-circle);
+.p-TabBar.theia-app-centers .p-TabBar-tab.p-mod-closable.a-mod-uncloseable.theia-mod-dirty > .p-TabBar-tabCloseIcon:before {
+  content: "\ea71";
 }
 
 .monaco-list-row.show-file-icons.focused {

Diff for: arduino-ide-extension/src/browser/theia/core/widget-manager.ts

@@ -66,6 +66,11 @@ export class WidgetManager extends TheiaWidgetManager {
     if (title.closable) {
       title.closable = false;
     }
+    // Show the dirty indicator on uncloseable widgets when hovering over the title. Instead of showing the `X` for close.
+    const uncloseableClass = 'a-mod-uncloseable';
+    if (!title.className.includes(uncloseableClass)) {
+      title.className += title.className + ` ${uncloseableClass}`;
+    }
   }
 
   /**