all space column names.

The parser has been modified to check VIEW column names
with the check_column_name function and to report an error
on empty and all space column names (same as for TABLE
column names).


sql/sql_yacc.yy:
  Fixed bug #27695.
  The parser has been modified to check VIEW column aliases
  with the check_column_name function and to report an error
  on empty columns and all space columns (same as for TABLE
  column names).
mysql-test/t/select.test:
  Updated test case for bug #27695.
mysql-test/r/select.result:
  Updated test case for bug #27695.