LibGUI+WindowServer: Add new WMEvent Super+Space

To make Assistant useful we need a way to quickly trigger it. I've
added a new specialized event coming from the window server for when a
user is holding down 'Super' and hits 'Space'.

The Taskbar will be able to listen for this event and spawn a new
instance of the Assistant if it's not already running.

Userland/Libraries/LibGUI/Event.h

@@ -63,6 +63,7 @@ public:
         WM_WindowIconBitmapChanged,
         WM_AppletAreaSizeChanged,
         WM_SuperKeyPressed,
+        WM_SuperSpaceKeyPressed,
         __End_WM_Events,
     };
 
@@ -102,6 +103,14 @@ public:
     }
 };
 
+class WMSuperSpaceKeyPressedEvent : public WMEvent {
+public:
+    explicit WMSuperSpaceKeyPressedEvent(int client_id)
+        : WMEvent(Event::Type::WM_SuperSpaceKeyPressed, client_id, 0)
+    {
+    }
+};
+
 class WMAppletAreaSizeChangedEvent : public WMEvent {
 public:
     explicit WMAppletAreaSizeChangedEvent(const Gfx::IntSize& size)

Userland/Libraries/LibGUI/WindowManagerServerConnection.cpp

@@ -57,4 +57,10 @@ void WindowManagerServerConnection::super_key_pressed(i32 wm_id)
     if (auto* window = Window::from_window_id(wm_id))
         Core::EventLoop::current().post_event(*window, make<WMSuperKeyPressedEvent>(wm_id));
 }
+
+void WindowManagerServerConnection::super_space_key_pressed(i32 wm_id)
+{
+    if (auto* window = Window::from_window_id(wm_id))
+        Core::EventLoop::current().post_event(*window, make<WMSuperSpaceKeyPressedEvent>(wm_id));
+}
 }

Userland/Libraries/LibGUI/WindowManagerServerConnection.h

@@ -32,6 +32,7 @@ private:
     virtual void window_rect_changed(i32, i32, i32, Gfx::IntRect const&) override;
     virtual void applet_area_size_changed(i32, Gfx::IntSize const&) override;
     virtual void super_key_pressed(i32) override;
+    virtual void super_space_key_pressed(i32) override;
 };
 
 }