Fix bug #16157, a crash when innodb_log_group_home_dir is set to an empty
string. This patch is from Heikki.

lock_rec_unlock(): Initialize local variable release_lock, in order to avoid
dereferencing an uninitialized pointer when no lock exists on rec.

This bug was introduced in r103 of branches/5.0, ported as r104 to trunk.

os_file_handle_error(): Map the error codes EXDEV, ENOTDIR, and EISDIR
to the new code OS_FILE_PATH_ERROR.  Treat this code as OS_FILE_PATH_ERROR.
This fixes the crash on RENAME TABLE when the .ibd file is a symbolic link
to a different file system.  (Bug #15991)

Do not log empty binlog file name at transaction commit.

trx_commit_off_kernel(): Do not write empty trx->mysql_log_file_name.

Protect the increment and decrement operations on the statistic variables
os_n_pending_writes and os_n_pending_reads with os_file_count_mutex.

Restore "make dist" for the header files in "innobase/include".

Fixed a bug on unlock_row. In a unlock_row we may unlock
only the latest lock granted to this transaction to the row.

Fix for BUG#11704: "Found locks from different thread" warnings:
 The source of warnings was this scenario in OPTIMIZE:

     thr1: lock table with TL_WRITE_ONLY (InnoDB converts lock to
     TL_WRITE_ALLOW_WRITE)

     thr2: (UPDATE command) obtains a TL_WRITE_ALLOW_WRITE lock

     thr1: call mysql_lock_abort(). This function sets type of thr'1 lock
     to TL_WRITE_ONLY

     thr2: try to release thr2's lock. See two locks: TL_WRITE_ONLY,
     TL_WRITE_ALLOW_WRITE and produce a warning.
   
The fix: Make InnoDB not to convert TL_WRITE_ONLY locks to
TL_WRITE_ALLOW_WRITE in OPTIMIZE TABLE.

Do not pad VARBINARY or BINARY columns. (Bug #14189)

innodb.test, innodb.result: Add test cases for foreign key constraints
between VARBINARY and BINARY columns, and between VARCHAR BINARY and
CHAR BINARY columns.

innobase_init(): Assert that
DATA_MYSQL_BINARY_CHARSET_COLL == my_charset_bin.number.

dtype_get_pad_char(): Do not pad VARBINARY or BINARY columns.

row_ins_cascade_calc_update_vec(): Refuse ON UPDATE CASCADE
when trying to change the length of a VARBINARY column
that refers to or is referenced by a BINARY column.  BINARY
columns are no longer padded on comparison, and thus they
cannot be padded on storage either.

Add tests for >1K keys on 32-bit platforms.

Clean up innodb_gis.test.

Key from branches/5.0.

index in the parent table rather than the index in the child table.
(Bug #15550)

innodb.test, innodb.result: Add test cases for foreign key errors.

In row_ins_set_detailed(), truncate the tmpfile by os_file_set_eof(), because
trx_set_detailed_error_from_file() does not call ftell() to determine
the actual length of the file.  This bug resulted in trash being appended
to foreign key error messages.

Work around Bug #12071: Do not call os_file_create_tmpfile() at runtime.
Instead, create all tempfiles at startup and guard access to them with
mutexes.

We new use TABLE_SHARE instead of TABLE when creating engine handlers.

innobase_savepoint():
  Replaced check which always failed due to similar check in caller
  with assertion.

Fixed compiler error for Win32 build.

#12701.

Synced from MySQL.

Make comments about buf_block_t::index more accurate.

Note that buf_block_t::index should be protected by btr_search_latch
or an s-latch or x-latch on the index page.
btr_search_drop_page_hash_index(): Read block->index while holding
btr_search_latch and use the cached value in the loop.  Remove some
redundant assertions.

Mostly fix bug #13778, when FOREIGN_KEY_CHECKS=0 we still need to check
that datatypes between foreign key references are compatible.

Add test cases (also for bug #9802).

to avoid warnings.

Adapt callers.