Analysis: Provided incorrect parameter to output buffer size
and incorrectly determined actual payload size after compression.

implementation.

    Merge https://github.com/kakao/mariadb-10.0 that contains Facebook's
    implementation for defragmentation

    facebook/mysql-5.6@a2d3a74
    facebook/mysql-5.6@def96c8
    facebook/mysql-5.6@9c67c5d
    facebook/mysql-5.6@921a81b
    facebook/mysql-5.6@aa519bd
    facebook/mysql-5.6@fea7d13
    facebook/mysql-5.6@09b29d3
    facebook/mysql-5.6@9284abb
    facebook/mysql-5.6@dbd623d
    facebook/mysql-5.6@aed55dc
    facebook/mysql-5.6@aad5c82

    This version does not add new SQL-syntax and new handler API function.
    Instead optimize table is mapped to defragment table if
    innodb_defragment=ON, by default the feature is off.

    Contains changes authored by Sunguck Lee (Kakao).

buf0buf.cc line 2642.

Analysis: innodb_compression_algorithm is a global variable and
can change while we are building page compressed page. This could
lead page corruption.

Fix: Cache innodb_compression_algorithm on local variable before
doing any compression or page formating to avoid concurrent
change. Improved page verification on debug builds.

Analysis: InnoDB writes also files that do not contain FIL-header.
This could lead incorrect analysis on os_fil_read_func function
when it tries to see is page page compressed based on FIL_PAGE_TYPE
field on FIL-header. With bad luck uncompressed page that does
not contain FIL-headed, the byte on FIL_PAGE_TYPE position could
indicate that page is page comrpessed.

Fix: Upper layer must indicate is file space page compressed
or not. If this is not yet known, we need to read the FIL-header
and find it out. Files that we know that are not page compressed
we can always just provide FALSE.

Added extra check for default_role column.

Also fixed wording on one message.

to avoid test failures.

# of processed files is printed every 15 sec.

compression format (Fusion-IO).

Addeed LZMA and BZIP2 compression methods.

in file buf0mtflu.cc line 570.

Analysis: Real timing bug, we should take the mutex before we
try to send those shutdown messages, that would make sure
that threads doing a unfinished flush (they have acquired
this mutex) have time to do their work before we add shutdown
messages to work queue. Currently, we just add those shutdown
messages to work queue and code assumes that at flush, there
is constant number of items to be processed and thus
leading to assertion.

Forgot the code

- Add support for DELETE .. RETURNING statement in ANALYZE code.

variables and reduce the number of ifdef's

- In print_explain_row(), do not forget to print r_rows.
- Switch Explain_update from using its own counters to re-using
  Table_access_tracker.
- Make ANALYZE UPDATE code structure uniform with ANALYZE DELETE.

add a comment

-Wl,-z,relro,-z,now
-pie
-fstack-protector --param=ssp-buffer-size=4
-D_FORTIFY_SOURCE=2

move MY_CHECK_C_COMPILER_FLAG and MY_CHECK_CXX_COMPILER_FLAG
to a separate file, introduce MY_CHECK_AND_SET_COMPILER_FLAG,
use it where possible.

This reverts commit 0bf9fd89.