server to crash".

Crash caused by assertion failure happened when one ran SHOW OPEN TABLES
while concurrently doing DROP TABLE (or RENAME TABLE, CREATE TABLE LIKE
or any other command that takes name-lock) in other connection.
For non-debug version of server problem exposed itself as wrong output
of SHOW OPEN TABLES statement (it was missing name-locked tables).
Finally in 5.1 both debug and non-debug versions simply crashed in
this situation due to NULL-pointer dereference.

This problem was caused by the fact that table placeholders which were
added to table cache in order to obtain name-lock had TABLE_SHARE::table_name
set to 0. Therefore they broke assumption that this member is non-0 for
all tables in table cache which was checked by assert in list_open_tables()
(in 5.1 this function simply relies on it).
The fix simply sets this member for such placeholders to appropriate value
making this assumption true again.

This patch also includes test for similar bug 12212 "Crash that happens
during removing of database name from cache" reappeared in 5.1 as bug 19403.

into  bodhi.local:/opt/local/work/mysql-5.0-runtime-merge

into  moonbone.local:/work/tmp_merge-5.0-opt-mysql

into  moonbone.local:/work/tmp_merge-5.0-opt-mysql

into  moonbone.local:/work/tmp_merge-5.0-opt-mysql

into  moonbone.local:/work/tmp_merge-5.0-opt-mysql

into  moonbone.local:/work/tmp_merge-4.1-opt-mysql

into  moonbone.local:/work/tmp_merge-4.1-opt-mysql

into  mysql.com:/home/hf/work/mysql-4.1.20317

into  bodhi.local:/opt/local/work/mysql-5.0-runtime-merge

into  lmy002.wdf.sap.corp:/home/georg/work/mysql/prod/mysql-5.0

  Delete: mysql-test/t/sp.test.orig

Fixes:
- bug #19834: Using cursors when running in READ-COMMITTED can cause InnoDB to crash
- bug #21112: InnoDB slow with > 100,000 .ibd files
- bug #21113: Duplicate printout in SHOW INNODB STATUS

into  neptunus.(none):/home/msvensson/mysql/mysql-4.1

into  rakia.(none):/home/kgeorge/mysql/autopush/B20103-5.0-opt

 - make the client to respect the server-side 
   no_backslash_escapes option and disable the 
   special meaning of backslash also at client side.

into  mysql.com:/users/lthalmann/bk/MERGE/mysql-5.0-merge

into  mysql.com:/users/lthalmann/bk/MERGE/mysql-4.1-merge

into  rakia.(none):/home/kgeorge/mysql/autopush/B11551-5.0-opt

into  sunlight.local:/local_work/tmp_merge-5.0-opt-mysql

into  mysql.com:/users/lthalmann/bk/MERGE/mysql-5.0-merge

into  mysql.com:/users/lthalmann/bk/MERGE/mysql-5.0-merge

into  mysql.com:/users/lthalmann/bk/MERGE/mysql-4.1-merge

into  weblab.(none):/home/marcsql/TREE/mysql-5.0-21269

  After merge fix

The problem was that the grammar allows to create a function with an optional
definer clause, and define it as a UDF with the SONAME keyword.
Such combination should be reported as an error.

The solution is to not change the grammar itself, and to introduce a
specific check in the yacc actions in 'create_function_tail' for UDF,
that now reports ER_WRONG_USAGE when using both DEFINER and SONAME.

into  rakia.(none):/home/kgeorge/mysql/autopush/B11551-5.0-opt

 
made DROP VIEW to continue on error and report an aggregated error 
 at its end. This makes it similar to DROP TABLE.

into  macbook.gmz:/Users/kgeorge/mysql/work/B21080-5.0-opt

  When executing ALTER TABLE all the attributes of the view were overwritten.
  This is contrary to the user's expectations.
  So some of the view attributes are preserved now : namely security and 
  algorithm. This means that if they are not specified in ALTER VIEW
  their values are preserved from CREATE VIEW instead of being defaulted.

into  neptunus.(none):/home/msvensson/mysql/mysql-4.1

into  neptunus.(none):/home/msvensson/mysql/mysql-4.1

into  neptunus.(none):/home/msvensson/mysql/mysql-4.1

 - Init start_lineno to 0

into  sunlight.local:/local_work/tmp_merge-5.0-opt-mysql

into  mysql.com:/Users/kent/mysql/bk/mysql-5.0