LibWeb: Do not return after ignoring a key event on an editable node

We do not want to blindly say we handled the key event. Otherwise, the
chrome is unable to handle shortcuts while an editable node is focused.

Userland/Libraries/LibWeb/Page/EventHandler.cpp

@@ -856,9 +856,6 @@ bool EventHandler::handle_keydown(KeyCode key, u32 modifiers, u32 code_point)
             m_browsing_context->increment_cursor_position_offset();
             return true;
         }
-
-        // NOTE: Because modifier keys should be ignored, we need to return true.
-        return true;
     }
 
     // FIXME: Work out and implement the difference between this and keydown.