Terminal+LibVT: Add "clear including history" action (Ctrl+Shift+K) :^)

Sometimes you just want to get rid of all your scrollback history in
the terminal, and now there's a way to do that.

Applications/Terminal/main.cpp

@@ -297,6 +297,9 @@ int main(int argc, char** argv)
     edit_menu.add_action(terminal.copy_action());
     edit_menu.add_action(terminal.paste_action());
 
+    auto& view_menu = menubar->add_menu("View");
+    view_menu.add_action(terminal.clear_including_history_action());
+
     GUI::ActionGroup font_action_group;
     font_action_group.set_exclusive(true);
     auto& font_menu = menubar->add_menu("Font");

Libraries/LibVT/Terminal.cpp

@@ -49,6 +49,14 @@ void Terminal::clear()
     set_cursor(0, 0);
 }
 
+void Terminal::clear_including_history()
+{
+    m_history.clear();
+    clear();
+
+    m_client.terminal_history_changed();
+}
+
 inline bool is_valid_parameter_character(u8 ch)
 {
     return ch >= 0x30 && ch <= 0x3f;

Libraries/LibVT/Terminal.h

@@ -59,6 +59,8 @@ public:
     void on_input(u8);
 
     void clear();
+    void clear_including_history();
+
     void set_size(u16 columns, u16 rows);
     u16 columns() const { return m_columns; }
     u16 rows() const { return m_rows; }

Libraries/LibVT/TerminalWidget.cpp

@@ -133,9 +133,15 @@ TerminalWidget::TerminalWidget(int ptm_fd, bool automatic_size_policy, RefPtr<Co
         paste();
     });
 
+    m_clear_including_history_action = GUI::Action::create("Clear including history", { Mod_Ctrl | Mod_Shift, Key_K }, [this](auto&) {
+        clear_including_history();
+    });
+
     m_context_menu = GUI::Menu::construct();
     m_context_menu->add_action(copy_action());
     m_context_menu->add_action(paste_action());
+    m_context_menu->add_separator();
+    m_context_menu->add_action(clear_including_history_action());
 }
 
 TerminalWidget::~TerminalWidget()
@@ -865,3 +871,8 @@ void TerminalWidget::did_change_font()
     if (!size().is_empty())
         relayout(size());
 }
+
+void TerminalWidget::clear_including_history()
+{
+    m_terminal.clear_including_history();
+}

Libraries/LibVT/TerminalWidget.h

@@ -79,9 +79,11 @@ public:
 
     GUI::Action& copy_action() { return *m_copy_action; }
     GUI::Action& paste_action() { return *m_paste_action; }
+    GUI::Action& clear_including_history_action() { return *m_clear_including_history_action; }
 
     void copy();
     void paste();
+    void clear_including_history();
 
     virtual bool accepts_focus() const override { return true; }
 
@@ -178,6 +180,7 @@ private:
 
     RefPtr<GUI::Action> m_copy_action;
     RefPtr<GUI::Action> m_paste_action;
+    RefPtr<GUI::Action> m_clear_including_history_action;
 
     RefPtr<GUI::Menu> m_context_menu;
     RefPtr<GUI::Menu> m_context_menu_for_hyperlink;