Redesigned the handler close functions so that they are usable
at different places where waiting for closing tables is done.


mysql-test/r/flush_table.result:
  bug#3565 - HANDLER and FLUSH TABLE/TABLES deadlock.
  Added the test results.
mysql-test/t/flush_table.test:
  bug#3565 - HANDLER and FLUSH TABLE/TABLES deadlock.
  Activated old test case.
  Added new test cases.
sql/mysql_priv.h:
  bug#3565 - HANDLER and FLUSH TABLE/TABLES deadlock.
  Made mysql_ha_close() more flexible.
  Removed mysql_ha_closeall(), which closed only one table despite its name.
  Added mysql_ha_close_list(), which closes the complete list or all tables and does not lock.
  Removed a duplicate declaration.
sql/sql_base.cc:
  bug#3565 - HANDLER and FLUSH TABLE/TABLES deadlock.
  Added proper close calls before some wait points to avoid deadlocks
  or infinite loops.
sql/sql_handler.cc:
  bug#3565 - HANDLER and FLUSH TABLE/TABLES deadlock.
  Redesigned the internal function find_table_ptr_by_name().
  It can now suppress locking and tells if the requested table
  has been flushed by itself.
  Extended mysql_ha_close() so that it can now suppres locking
  and error reporting. That way it can be used at more places and the
  old function mysql_ha_closeall() is now obsolete.
  Added a new function mysql_ha_close_list() which closes a whole list
  of HANDLER tables or all HANDLER tables, if the list is NULL.
  Furthermore is can close all 'old' (marked for flush) HANDLER tables.
sql/sql_table.cc:
  bug#3565 - HANDLER and FLUSH TABLE/TABLES deadlock.
  Replaced the obsolte mysql_ha_closeall() by the new mysql_ha_close().