Fixing non-BMP characters to have the same weight, as it was before
MDEV-8418 and MDEV-8417.

MDEV-8418 utf16: compare broken bytes as "greater than any non-broken character"

function used incorrect type.

Fixes over the original patch:
- Fix variable/class/other names
- Fix the JSON output to be in line with the output of other JSON
  constructs we produce

Used wrong type for encryption_key_id and page_compression_level in
table options. Make explicit casts for calls also.

mysqld--help was not updated for binlog row image.

Logic error, NULL pointer was referenced.

File block size might be 0 and used on modulo operator. Make sure that
file block size is initialized to 512.

When writing rows with a minimal row image, it is possible to receive
empty events. In that case m_curr_row and m_rows_end are the same,
however the event implies an insert into the table with the default
values associated for that table.

Due to how events are created with a minimal binlog_row_image, it is
possible to receive empty write events because all the columns
in the table have a default value. (For example an auto-increment)
Make sure we account for that.

Update_rows_log_event must make use of the after image bitmap when
detecting which columns to update.

The bitmap is now deduced from the table's read and write set.

The logging function now writes to the binlog according
to the bitmap columns implied by the binlog_row_image variable.

The row events no longer require columns arguments.

When deciding which binlog events are pending, make use of the bitmap
compare function instead.

The function compares bitmaps according to the binlog_row_image variable
setting.

The rpl_injector code is now considered dead code.

This patch only removes the minimum number of function calls
to allow implementing binlog_row_image. The other functions are to be
removed in a subsequent patch.

Depending on which binlog_row_image we are using, we must
mark columns which to update differently both in the before image
as well as the after image.

The system variable is present but it does not do anything yet.

of wsrep_provider_options' value. Also increase the max value
length for SYSTEM_VARIABLES schema table.