clear views cache on admin/build/modules

in working on views-support for signup.module, i've run into some tricky problems with the view cache and default views from other modules. basically, if your views support is conditionally loaded in hook_menu() in your primary module, not stuffed into a totally separate signup_views.module or something, then it's really hard for your module to export default views and have that work automatically without the admin needing to manually clear their views cache.

i tried something fancy like this:

function views_form_alter($form_id, &$form) {
  if ($form_id == 'profile_field_form') {
    views_invalidate_cache();
  }
  if ($form_id == 'system_modules') {
    $form['#submit']['views_system_modules_submit'] = array();
  }
}

function views_system_modules_submit($form_id, $form_values) {
  views_invalidate_cache();
  drupal_set_message("Cleared views cache");
}

and even that didn't work, due to the timing of when things are loaded and run. :( so, this seems to be the only fool-proof solution:

function views_form_alter($form_id, &$form) {
  if ($form_id == 'profile_field_form' || $form_id == 'system_modules') {
    views_invalidate_cache();
  }
}

in other words, *always* clear the views cache, even if you just view the admin/build/modules page. ;) works fine. i'm not sure if this is a major performance problem, but it certainly makes things work more correctly without manual effort on the part of the admin.