LibWeb: Allow inserting text at the cursor by typing characters :^)

This works everywhere right now, but it's obviously not going to stay
that way forever. :^)

Note that this does not advance the cursor correctly for whitespace
since the cursor is DOM-based and doesn't take whitespace collapsing
into account yet.

Libraries/LibWeb/PageView.cpp

@@ -335,6 +335,8 @@ void PageView::mouseup_event(GUI::MouseEvent& event)
 
 void PageView::keydown_event(GUI::KeyEvent& event)
 {
+    page().handle_keydown(event.key(), event.modifiers(), event.code_point());
+
     if (event.modifiers() == 0) {
         switch (event.key()) {
         case Key_Home: