Before this fix, the performance schema instrumentation
in mdl.h / mdl.cc was incomplete, causing:
- build warnings,
- no data collection for the performance schema

This fix:
- added instrumentation helpers for the new preferred
  reader read write lock, mysql_prlock_*
- implemented completely the performance schema
  instrumentation of mdl.h / mdl.cc

Set $glob_bindir, like $bindir in v2
Removed some obsolete IM code rather than changing it

Before this fix, mysql_upgrade would always drop and re create
the performance_schema database.
This in theory could destroy user data created using 5.1 or older versions.

With this fix, mysql_upgrade checks the content of the
performance_schema database before droping it.

Fix for BUG#51215 "log-error partially works with version 5.5": WL 4738 (reengineering of server variables)
had broken the 5.1 behaviour of --log-error: --log-error without argument sent to stderr instead of writing
to a file with an autogenerated name.

The unit test pfs_instr-t:
- generates a very long (10,000) bytes file name
- calls find_or_create_file.

This leads to a buffer overflow in mysys in my_realpath(),
because my_realpath and mysys file APIs in general do not
test for input parameters: mysys assumes every file name
is less that FN_REFLEN in length.

Calling find_or_create_file with a very long file name is likely
to happen when instrumenting third party code that does not use mysys,
so this test is legitimate.

The fix is to make find_or_create_file in the performance schema
more robust in this case.

The root cause of the failure is that when
Bug#51447 performance schema evil twin files
was fixed, instrumented file names got normalized.

The pfs-t unit test depends on this file normalization,
but it was not updated.

This fix aligns pfs-t.cc lookup_file_by_name()
with the logic in pfs_instr.cc find_or_create_file().

and "README" (header part: "This is a release of MySQL ...")
from "trunk" to "next-mr".

by adding the header part "This is MySQL ...".

the license remains to be the GPL Version 2, June 1991

This is *no* change in contents, the differences are formatting only
and an address update of the FSF. It continues to be Version 2, June 1991.

Bug#51676 Server crashes on SELECT, ORDER BY on 'utf8mb4' column
An additional fix. We should use 0xFFFD as a weight for supplementary
characters, not the "weight for character U+FFFD".

Using latin1 client character set for ASCII locales:
- because ascii is not a build-in character set
- for better backward compatibility

Bug#51675 Server crashes on inserting 4 byte char. after ALTER TABLE to 'utf8mb4' 
Bug#51676 Server crashes on SELECT, ORDER BY on 'utf8mb4' column

(fails on pb for solaris debug_max)

when cmake is used for building in a symlinked directory, 
and confguration is later adjusted with "cmake-gui ." After it,
GenServerSource fails with "no rule for <filename>". The reason
for the error is that cmake-gui  resolves "." as realpath and rules
are generated accordingly, while "cmake" used symlinked path

The fix uses ${CMAKE_CURRENT_BINARY_DIR} instead of 
${CMAKE_BINARY_DIR}/sql  for generated files. 
This causes CMake to use relative file names so 
relative file names when generating make rules.
Using relative filenames avoids the problem of 
refering to the same directory using 2 different paths.

Besides, using ${CMAKE_CURRENT_BINARY_DIR} is 
a commonly used style when working with generated 
files.

autotools runs
- Fix recognition of --with-debug=full in configure wrapper
- Remove CMakeCache.txt in configure wrapper, to match the original
- Fix recognition of max-no-ndb
- Fix broken dependencies of mysql_fix_privilege_table.sql from 
  mysql_system_tables.sql and mysql_system_tables_fix.sql
- Add "distclean target" that informs user about appropriate bzr command

           Diagnostics_area::set_ok_status on DROP FUNCTION

This assert tests that the server is not trying to send "ok" to
the client if an error has occured during statement processing.

In this case, the assert was triggered by lock timeout errors when
accessing system tables to do an implicit REVOKE after executing
DROP FUNCTION/PROCEDURE. In practice, this was only likely to
happen with very low values for "lock_wait_timeout" (in the bug report
1 second was used). These errors were ignored and the server tried
to send "ok" to the client, triggering the assert.

The patch for Bug#45225 introduced lock timeouts for metadata locks.
This made it possible to get timeouts when accessing system tables.
Note that a followup patch for Bug#45225 pushed after this
bug was reported, changed accessing of system tables such
that the user-supplied timeout value is ignored and the maximum
timeout value is used instead. This exact bug was therefore
only noticeable in the period between the initial Bug#45225 patch
and the followup patch.

However, the same problem could occur for any errors during revoking
of privileges - not just timeouts. This patch fixes the problem by
making sure that any errors during revoking of privileges are
reported to the client. 

Test case added to sp-destruct.test. Since the original bug is not
reproducable now that system tables are accessed using a a long
timeout value, this test instead calls DROP FUNCTION with a grant
system table missing.

Conflicts:
  - sql/sql_base.cc