Highlighter: update all editors after downloading additional definitions

Instead of just the editor with the info bar that was triggering the
download action or none editor if the action was triggered from the
settings dialog.

Change-Id: I4158eeb7fdb0a763d082c6d801b400e8635c7f38
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/texteditor/highlighter.cpp

@@ -260,6 +260,7 @@ void Highlighter::downloadDefinitions(std::function<void()> callback) {
                 Core::MessageManager::write(tr("Highlighter updates: done"),
                                             Core::MessageManager::ModeSwitch);
                 downloader->deleteLater();
+                reload();
                 if (callback)
                     callback();
             });

src/plugins/texteditor/texteditor.cpp

@@ -3104,10 +3104,7 @@ void TextEditorWidgetPrivate::updateSyntaxInfoBar(const Highlighter::Definitions
                           InfoBarEntry::GlobalSuppression::Enabled);
         info.setCustomButtonInfo(BaseTextEditor::tr("Download Definitions"), [missing, this]() {
             m_document->infoBar()->removeInfo(missing);
-            Highlighter::downloadDefinitions([widget = QPointer<TextEditorWidget>(q)]() {
-                if (widget)
-                    widget->configureGenericHighlighter();
-            });
+            Highlighter::downloadDefinitions();
         });
 
         infoBar->removeInfo(multiple);