MDEV-19940 Clean up INFORMATION_SCHEMA.INNODB_ tables
Shorten some VARCHAR attributes to a more reasonable length.
INNODB_METRICS: Rename the column STATUS to ENABLED, and make it Boolean.
Replace with INT(1) many Boolean attributes that were declared as VARCHAR
containing 'NO','YES','disabled','enabled','Uninitialized','Initialized'.
Replace some VARCHAR attributes with ENUM.
Replace some BIGINT with INT when 32 bits are sufficient.
Remove INNODB_SYS_TABLESPACES.SPACE_TYPE. The type of a tablespace
can be derived from the tablespace ID. A fixed number is used for
the system tablespace and the temporary tablespace. All other tablespaces
are single-table or single-partition tablespaces.
i_s_locks_row_t::lock_type, lock_get_type_str(): Remove.
This is a redundant field. Table and record locks can be
distinguished by whether i_s_locks_row_t::lock_index is NULL.
fill_trx_row(): Do not unnecessarily copy the constant strings that
trx->op_info is pointing to.
i_s_locks_row_t::lock_mode: Replace string with integer.
Fix the build on clang. GCC only checks that a member function with
the C++11 override keyword is actually overriding a virtual member
function in a base class. In clang, you will get a warning for
overridden member functions that lack the keyword, if any overridden
member function of the class is declared with the keyword.
Fix build failure on CentOS for MariaDB official CI
The gcc version in CentOS 7 is 4.8.2 (released in Mar 2013).
But Arm added the support for 'arm_acle.h' in gcc 5.1 (released in Jun 2014).
And there are also some bugs in Arm gcc 4.8.
The patch is to detect GCC(greater than 5.1) version for Arm crc32c.
