exposed_filter_applied not working correctly leading to form not being processed

This issue is related to #1877678: Exposed filter gets error class without submitting it.

The fix there makes 'always_process' dependent on the value of exposed_filter_applied(). But it also provides a new implementation of that function which uses get_exposed_input() to check if a filter has been applied (i.e. has a value or not).

The problem with better exposed filters is that it also uses its own implementation of exposed_filter_applied(), which checks if $view->exposed_input[] has a value. For my exposed form which has no required input (if that would matter) the check returns false (i.e. the array $view->exposed_input[] has no value), even if I submitted a value for the filter.
This leads to the form not being properly processed, since $form_state['input']['form_id'] would not be set in form.inc line 873, because $form_state['always_process'] is FALSE in form.inc line 868. Because the form_id is not set, the check in form.inc line 1834 would set $form_state['process_input'] to FALSE. This in turn would lead to the check in form.inc line 888 to fail, which means the form is not being processed. And there you go :)

So the fix would be to either also check get_exposed_input(), like the patch in #1877678: Exposed filter gets error class without submitting it does, OR to NOT have our own implementation of exposed_filter_applied() and just use the parent implementation which the patch in #1877678: Exposed filter gets error class without submitting it provides.