litehtml viewer: Show link targets in tool tip

Like done for the other backends.

Fixes: QTCREATORBUG-23027
Change-Id: Idc1f7ee2f6240e6c488a9d7d65ead3be6846d303
Reviewed-by: Jarek Kobus <jaroslaw.kobus@qt.io>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

src/plugins/help/litehtmlhelpviewer.cpp

@@ -16,6 +16,7 @@
 #include <QGuiApplication>
 #include <QScrollBar>
 #include <QTimer>
+#include <QToolTip>
 #include <QVBoxLayout>
 #include <QWheelEvent>
 
@@ -100,6 +101,11 @@ LiteHtmlHelpViewer::LiteHtmlHelpViewer(QWidget *parent)
             &QLiteHtmlWidget::contextMenuRequested,
             this,
             &LiteHtmlHelpViewer::showContextMenu);
+    connect(m_viewer, &QLiteHtmlWidget::linkHighlighted, this, [this](const QUrl &url) {
+        m_highlightedLink = url;
+        if (!url.isValid())
+            QToolTip::hideText();
+    });
     auto layout = new QVBoxLayout;
     setLayout(layout);
     layout->setContentsMargins(0, 0, 0, 0);
@@ -284,6 +290,12 @@ bool LiteHtmlHelpViewer::eventFilter(QObject *src, QEvent *e)
             goForward(1);
             return true;
         }
+    } else if (e->type() == QEvent::ToolTip) {
+        auto he = static_cast<QHelpEvent *>(e);
+        if (m_highlightedLink.isValid())
+            QToolTip::showText(he->globalPos(),
+                               m_highlightedLink.toDisplayString(),
+                               m_viewer->viewport());
     }
     return HelpViewer::eventFilter(src, e);
 }

src/plugins/help/litehtmlhelpviewer.h

@@ -4,11 +4,11 @@
 #pragma once
 
 #include "helpviewer.h"
-#include "openpagesmanager.h"
 
 #include <qlitehtmlwidget.h>
 
 #include <QTextBrowser>
+#include <QUrl>
 
 #include <optional>
 
@@ -68,6 +68,7 @@ private:
     QLiteHtmlWidget *m_viewer;
     std::vector<HistoryItem> m_backItems;
     std::vector<HistoryItem> m_forwardItems;
+    QUrl m_highlightedLink;
 };
 
 }   // namespace Internal