ClangCodeModel: Missing file "ui_mainwindow.h" marked as error

1. Enable the ClangCodeModel plugin.
2. Create a new Qt Widgets Application project.
3. Open the file mainwindow.cpp.
   The line

   #include "ui_mainwindow.h"
   

   is marked as an error: "fatal error: 'ui_mainwindow.h' file not found"

While this is technically correct, it is nothing the user could fix. The file will be created when building the project, so I think this error message is confusing. It should be hidden.