Wrong comparing method were choosen which results in false comparison.

Make Item_bool_func2::fix_length_and_dec() to get type and field from
real_item() to make REF_ITEM pass the check. 


sql/item_cmpfunc.cc:
  Fix bug#11325 Wrong date comparison in views
mysql-test/t/view.test:
  Test case for bug#11325 Wrong date comparison in views.
mysql-test/r/view.result:
  Test case for bug#11325 Wrong date comparison in views.