Write a log event to the general log before executing a statemment in PS mode
This change fixes failure of the test main.log_tables when it is run in PS mode
Updated the test main.events_logs_tests to query mysql.general_log
for the command_type 'Query' and 'Execute' in order to have consistent
test result both in case the test is run with --ps-protocol and without it
This patch changes the main name of 3 byte character set from utf8 to
utf8mb3. New old_mode UTF8_IS_UTF8MB3 is added and set TRUE by default,
so that utf8 would mean utf8mb3. If not set, utf8 would mean utf8mb4.
Remove usage of deprecated variable storage_engine. It was deprecated in 5.5 but
it never issued a deprecation warning. Make it issue a warning in 10.5.1.
Replaced with default_storage_engine.
