Fixing selection issues in Firefox

lib/web_ui/lib/src/engine/text_editing.dart

@@ -341,6 +341,9 @@ class TextEditingElement {
       _subscriptions.add(domElement.onKeyUp.listen((event) {
         _handleChange(event);
       }));
+      /// In Firefox the context menu item "Select All" does not work without
+      /// listening onSelect. On the other browersers onSelectionChange is
+      /// enough for covering "Select All" functionality.
       _subscriptions.add(domElement.onSelect.listen(_handleChange));
     } else {
       _subscriptions.add(html.document.onSelectionChange.listen(_handleChange));

lib/web_ui/test/text_editing_test.dart

@@ -76,7 +76,8 @@ void main() {
       expect(editingElement.domElement, input);
 
       // Input is appended to the glass pane.
-      expect('${editingElement.domElement.parent.tagName}', 'FLT-GLASS-PANE');
+      expect(domRenderer.glassPaneElement.contains(editingElement.domElement),
+          isTrue);
 
       editingElement.disable();
       expect(