Ladybird: Implement JS console input history

One can now use KeyUp and KeyDown to navigate through the already run
commands in the JS console.

Ladybird/ConsoleWidget.h

@@ -12,6 +12,7 @@
 #include <AK/DeprecatedString.h>
 #include <AK/Function.h>
 #include <AK/Vector.h>
+#include <QLineEdit>
 #include <QWidget>
 
 class QLineEdit;
@@ -48,4 +49,21 @@ private:
     bool m_waiting_for_messages { false };
 };
 
+class ConsoleInputEdit final : public QLineEdit {
+    Q_OBJECT
+public:
+    ConsoleInputEdit(QWidget* q_widget, ConsoleWidget& console_widget)
+        : QLineEdit(q_widget)
+        , m_console_widget(console_widget)
+    {
+    }
+
+private:
+    virtual void keyPressEvent(QKeyEvent* event) override;
+
+    ConsoleWidget& m_console_widget;
+    Vector<DeprecatedString> m_history;
+    size_t m_history_index { 0 };
+};
+
 }